Transparent polymer blends and articles prepared therefrom

ABSTRACT

Disclosed are polymer compositions having high transparency and low haze comprising immiscible blends of one or more thermoplastic polymers selected from polyesters, polycarbonates, and polyarylates, and a copolyamide or a transamidized, homogeneous blend of a least two polyamides. The components of the immiscible blend which have refractive indices which differ by about 0.006 to about −0.0006. The small difference in the refractive indices enable the incorporation of regrind into the polymer composition to produce transparent shaped articles. The blends of the present invention are useful in producing shaped articles such as, for example, sheeting, films, tubes, bottles, preforms and profiles. These articles may have one or more layers and can exhibit improved excellent barrier properties and good melt processability while retaining excellent mechanical properties. Metal catalysts can be incorporated into the compositions to produce oxygen-scavenging compositions.

CROSS REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of U.S. Non-Provisional applicationSer. Nos. 11/363,375, filed Feb. 27, 2006 and 11/363,374, filed Feb. 27,2006, each of which claim the benefit of U.S. Provisional ApplicationSer. Nos. 60/657,746, filed Mar. 2, 2005, and 60/657,747, filed Mar. 2,2005, each of which are incorporated herein by reference in theirentirety.

FIELD OF THE INVENTION

This invention pertains to transparent, immiscible polymer blendscomprising at least two polymer components. Specifically, this inventionrelates to immiscible blends comprising at least one thermoplasticpolymer and a copolyamide or a homogeneous blend of at least twopolyamides in which the different phases of the immiscible blend havesmall differences in the absolute value of their refractive indices.This invention also pertains to shaped articles comprising theimmiscible blends in which the refractive indices of the polymercomponents are closely matched.

BACKGROUND OF THE INVENTION

Many products, in particular food products, are sensitive to thepresence of oxygen and the loss or absorption of water. Packagedproducts with this sensitivity are susceptible to deterioration becauseof exposure to oxygen or absorption of moisture. Packaging materialswhich limit oxygen exposure to food articles, for example, help tomaintain the quality of the food articles and to reduce spoilage. Theuse of such barrier packaging thus keeps the article in inventory longerand thereby reduces restocking costs and waste. Attempts to solve thisproblem have led to the widespread use of oxygen barriers and/ormoisture barriers in packaging materials. Many polymeric materials areknown to act as barriers to oxygen or moisture. For example, typicalmoisture barriers include polyethylene and polypropylene. Representativeoxygen barriers include poly(ethylene vinyl alcohol) (“EVOH”),poly(vinyl alcohol) (“PVOH”), polyamides (nylons), and blends of thesematerials. Poly(vinylidene chloride), vinyl chloride copolymers, andvinylidene chloride-methyl acrylate copolymers also are useful asmoisture and oxygen barriers.

These conventional barrier materials, however, are expensive and haveunstable structural characteristics or other deficiencies that makefabrication of packaging materials solely out of barrier materialsdifficult or undesirable. For example, EVOH, while having superioroxygen barrier properties, is not effective as a moisture barrier. Otherbarrier materials are prohibitively expensive to be used solely as apackaging material. To avoid these problems, it has become a commonpractice to use multilayer structures in which the amount of expensivebarrier material may be reduced to a thin layer and used in conjunctionwith an inexpensive polymer on one or both sides of the barrier layer asstructural layers. The use of multilayer structures also helps toprotect the barrier layer from deterioration by structural layers.Multilayer products, however, can be expensive to produce. Further,multilayer articles can present difficulties in recycling because thedifferent polymer components are difficult to separate. In addition,blending the recovered scrap polymer or “regrind” with virgin polymeroften will cause unsatisfactory haze or opaqueness because of theincompatibility of the virgin materials with the regrind.

The shortcomings of conventional barrier polymers also may be overcomeby using a blend of the barrier polymer with another polymer.Unfortunately, as noted above, many blends of barrier polymers and otherthermoplastic polymers are immiscible and are opaque or hazy. Suchblends are not satisfactory for applications requiring clarity such as,for example, beverage containers.

Polyester polymers such as, for example, poly(ethylene terephthalate)(“PET”), are commonly used in packaging applications. PET has a numberof properties that make it useful as a packaging material, includingacceptable carbon dioxide barrier properties for soft drinks packaged inbottles containing multiple servings. However, improvements in thecarbon dioxide barrier of PET are needed for soft drinks packaged insmaller bottles and in its oxygen barrier, which is not well-suited forpackaging oxygen sensitive products such as, for example, beer, citrusproducts, tomato-based products, and aseptically packed meat.Poly(ethylene naphthalate) (“PEN”) is 3-10 times more effective as abarrier than PET but is more expensive.

Multilayer structures can be used to improve the gas barriercharacteristics of PET. For example, polymers that have excellent oxygenbarrier (also referred to as “passive barrier”) or scavenging properties(also referred to as “active barrier”) may be combined with PET toproduce a layered structure consisting of the individual polymers. Thesemultilayer structures, however, are expensive to produce. Blends ofbarrier polymers with PET also have been used to improve the oxygenbarrier of packages but, as noted above, often have poor transparencyand are not suitable for many packaging applications. The poortransparency of blends also makes it difficult to recycle manufacturingscrap from polymer blends into virgin polymer.

Copolyester films and extrusion blow molded (“EBM”) bottles are oftendesired for toughness, and are commonly used instead of PET forextrusion blow molding and film applications. These applications oftenrequire barrier that is comparable to that of oriented PET.Unfortunately, however, the barrier properties of copolyesters areinferior to oriented PET. Multilayer structures can be produced bycoextruding a thin, barrier film into the center of a thicker bulkstructure to improve the overall barrier. To be economical, however, EBMand film processes typically require that high levels (up to 80%) ofregrind (i.e., flash and trim) are reprocessed. Unfortunately, typicalbarrier materials are not miscible with copolyesters and blends of thesebarrier polymers with polyesters often show a high level of haze andpoor clarity. The haze level of the overall film structure, therefore,is increased to unacceptable levels when scrap polymer (i.e., regrind)is incorporated back into the primary layer.

A polymer blend that provides good passive and/or active barrierproperties, is economical, and can be recycled efficiently is needed inthe art. Such blends should be transparent, contain thermoplastic andbarrier polymers that provide a high barrier for oxygen, water, andcarbon dioxide, and can be used economically in article formingprocesses which incorporate a high level of regrind. In addition, thereis need for barrier and thermoplastic polymer compositions that can beused to economically produce multilayered articles having hightransparency and can tolerate a high level of regrind.

SUMMARY OF THE INVENTION

Polymer compositions having high transparency and high barrierproperties can be prepared from a immiscible blend of one or morethermoplastic polymers and a copolyamide or a homogeneous, transamidizedblend of at least 2 polyamides in which the difference in refractiveindex between the polyamide component and thermoplastic polymercomponent is about 0.006 to about −0.0006. Thus, the present inventionprovides a polymer composition, comprising an immiscible blend of:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a homogeneous, transamidized    blend of at least 2 polyamides;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less.

The first component comprises at least one thermoplastic polymerselected from polyesters, polycarbonates, polyarylates, and homogeneousblends of these polymers, while the second component comprises a blendof at least 2 polyamides which have been transamidized to produce ahomogeneous blend. We have discovered that refractive indices of thefirst and second components can be closely matched by selecting at least2 polyamides having different levels of aliphatic and aromatic residuesand transamidizing these polyamides to form a homogeneous blend. Thus,homogeneous blends of the thermoplastic polymers and the polymamides canbe used to tailor refractive indices of the second component and thefirst component to within their desired ranges such that the differencein refractive indices is about 0.006 to about −0.0006. For example, ahomogeneous blend of a polyester and a polycarbonate comprising theresidues of bisphenol A can be used as the first component and atransamidized, homogeneous blend of first polyamide comprising theresidues of m-xylylenediamine and adipic acid, and a second aliphaticpolyamide can be used as the barrier polymer. When the refractiveindices are thus matched, the first and second components form clear,immiscible blends that are suitable for the preparation of high clarity,shaped articles that can be used in many packaging applications.Multilayered articles may also be prepared by a variety of processesknown in the art. For example, the first and second components may becoextruded or coinjected from the melt into separate layers, or thelayers may be formed individually and brought together in a subsequentprocess such as, for example, lamination.

The second component can also comprise a copolyamide having a ratio ofaromatic and aliphatic dicarboxylic acid and diamine residues that canbe varied to closely match the refractive indices of the first andsecond components. Thus, another aspect of the invention is a polymercomposition, comprising an immiscible blend of:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a copolyamide;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less.

Another aspect of our invention is a polymer composition comprising animmiscible blend prepared by a process comprising melt blending:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a homogeneous, transamidized    blend of at least 2 polyamides;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less.

The compositions of our invention show excellent barrier properties. Theoxygen barrier properties may be enhanced by incorporating transitionmetal catalysts such as, for example, cobalt, manganese, iron,ruthenium, copper, nickel, palladium, and platinum into the blends toproduce oxygen scavenging compositions. The invention, thus, furtherprovides an oxygen-scavenging composition comprising:

-   (A) an immiscible blend comprising    -   (i) first component comprising at least one thermoplastic        polymer selected from polyester, polycarbonate, polyarylate, and        homogeneous blends thereof;    -   (ii) a second component comprising a transamidized, homogeneous        blend of at least two polyamides;        -   wherein the second component (ii) and the first            component (i) have a difference in refractive index,            RI(second component)−RI(first component), of about 0.006 to            about −0.0006, and the immiscible blend has a percent            transmittance of at least 75%, and a haze of 10% or less;            and-   (B) at least one metal selected from Groups 3-12, Rows 4-6 of the    Periodic Table of the Elements. Typical metal catalysts are cobalt,    manganese, and iron.

The blends of the present invention are useful for producing clear,shaped articles having improved barrier properties, melt processability,and excellent mechanical properties, and which can be prepared using ahigh proportion of regrind to virgin polymer. These shaped articles mayhave a single layer or multiple layers and have numerous packagingapplications. Accordingly, the invention further provides a process forforming a shaped article, comprising:

-   (A) melt blending    -   (i) a first component comprising at least one thermoplastic        polymer selected from polyesters, polycarbonates, polyarylates,        and homogeneous blends thereof; and    -   (ii) a second component comprising a copolyamide or a        homogeneous, transamidized blend of at least 2 polyamides;    -   wherein the first component (i) and second component (ii) form        an immiscible blend, the second component and the first        component have a difference in refractive index, RI(second        component)−RI(first component), of about 0.006 to about −0.0006,        and the immiscible blend has a percent transmittance of at least        75%, and a haze of 10% or less;-   (B) forming a shaped article;-   (C) recovering a scrap polymer composition comprising the blended    first and second components (i) and (ii);-   (D) grinding the scrap polymer composition to produce a polymer    regrind;-   (E) optionally, drying the scrap polymer composition; and-   (F) combining the polymer regrind with the first and second    components (i) and (ii) of step (A). Examples of shaped articles    which may be prepared by the process of the invention include, but    are not limited to, sheets, films, tubes, bottles, or profiles. The    shaped article may be produced by extrusion, calendering,    thermoforming, blow-molding, extrusion blow-molding, injection    molding, compression molding, casting, drafting, tentering, or    blowing.

The shaped articles may have a one or more layers comprising animmiscible blend of the first and second components or can have multiplelayers in which the first and second components are in separate layers.The invention also provides a multilayered, shaped article, comprising:

-   (i) a first layer comprising at least one thermoplastic polymer    selected from polyester, polycarbonate, polyarylate, and homogeneous    blends thereof; and-   (ii) a second layer comprising a transamidized homogeneous blend of    at least two polyamides;    wherein the second layer (ii) and the first layer (i) have a    difference in refractive index, RI(second layer)−RI(first layer), of    about 0.006 to about −0.0006, and the shaped article has a percent    transmittance of at least 75%, and a haze of 10% or less.

The invention further provides a process for forming a multilayeredshaped article, comprising:

-   (i) heating a first component comprising at least one thermoplastic    polymer selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof to a temperature of about Tg+100° C. to    about Tg+300° C. of the first component;-   (ii) heating a second component comprising a copolyamide or a    transamidized, homogeneous blend of at least two polyamides to a    temperature of about Tg+100° C. to about Tg+300° C. of the second    component;-   (iii) forming a shaped article having the first and second    components in separate layers;-   (iv) recovering scrap first and second components;-   (v) grinding the scrap first and second components to produce a    regrind;-   (vi) optionally, drying the regrind; and-   (vii) combining the regrind with the first component, second    component, or a combination thereof, of steps (i) and (ii);    wherein the second component of step (ii) and the first component of    step (i) of have a difference in refractive index, RI(second    component)−RI(first component), of about 0.006 to about −0.0006, and    the shaped article has a percent transmittance of at least 75%, and    a haze of 10% or less. The regrind may be incorporated into the    first or second layer and may be from about 5 to about 60 weight    percent of the article.

DETAILED DESCRIPTION

Polymer compositions having high clarity and good barrier properties canbe prepared from an immiscible blend of one or more thermoplasticpolymers and a transamidized, homogeneous blend of at least twopolyamides, in which the difference in refractive index between theblend of polyamides and the thermoplastic polymers is about 0.006 toabout −0.0006. The immiscible blend has a percent transmittance of atleast 75%, and a haze of 10% or less. In a general embodiment, thepresent invention provides polymer composition, comprising an immiscibleblend of:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a homogeneous, transamidized    blend of at least 2 polyamides;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less. The thermoplastic polymers and polyamides may be selected    from a wide variety of polymers. The refractive indices of the    second component and the first component can be adjusted to give a    difference of about 0.006 to about −0.0006 by the selection and    ratio of the polyamides of the second component or, alternatively,    by blending the thermoplastic polymers of the first component to    form a homogeneous blend. Our novel compositions can be used to    manufacture shaped articles having one or more layers such as, for    example, sheets, films, tubes, bottles, and profiles. The shaped    article may be produced by extrusion, calendering, thermoforming,    blow-molding, extrusion blow-molding, injection molding, compression    molding, casting, drafting, tentering, or blowing. Multilayer    articles can be prepared in which the immiscible blend is present in    one or more layers or the first and second components are in    separate layers. Because of the small difference in the refractive    indices of the first and second components, shaped articles prepared    from the composition of the invention can incorporate substantial    quantities of regrind and retain good transparency. The clarity and    barrier properties of these shaped articles produced make them    particularly useful for packaging applications.

Unless otherwise indicated, all numbers expressing quantities ofingredients, properties such as molecular weight, reaction conditions,and so forth used in the specification and claims are to be understoodas being modified in all instances by the term “about.” Accordingly,unless indicated to the contrary, the numerical parameters set forth inthe following specification and attached claims are approximations thatmay vary depending upon the desired properties sought to be obtained bythe present invention. At the very least, each numerical parametershould at least be construed in light of the number of reportedsignificant digits and by applying ordinary rounding techniques.Further, the ranges stated in this disclosure and the claims areintended to include the entire range specifically and not just theendpoint(s). For example, a range stated to be 0 to 10 is intended todisclose all whole numbers between 0 and 10 such as, for example 1, 2,3, 4, etc., all fractional numbers between 0 and 10, for example 1.5,2.3, 4.57, 6.1113, etc., and the endpoints 0 and 10. Also, a rangeassociated with chemical substituent groups such as, for example, “C₁ toC₅ hydrocarbons,” is intended to specifically include and disclose C₁and C₅ hydrocarbons as well as C₂, C₃, and C₄ hydrocarbons.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements.

As used in the specification and the appended claims, the singular forms“a,” “an” and “the” include their plural referents unless the contextclearly dictates otherwise. For example, reference a “polymer,” or a“shaped article,” is intended to include the processing or making of aplurality of polymers, or articles. References to a compositioncontaining or including “an” ingredient or “a” polymer is intended toinclude other ingredients or other polymers, respectively, in additionto the one named.

By “comprising” or “containing” or “including” we mean that at least thenamed compound, element, particle, or method step, etc., is present inthe composition or article or method, but does not exclude the presenceof other compounds, catalysts, materials, particles, method steps, etc,even if the other such compounds, material, particles, method steps,etc., have the same function as what is named, unless expressly excludedin the claims.

It is also to be understood that the mention of one or more method stepsdoes not preclude the presence of additional method steps before orafter the combined recited steps or intervening method steps betweenthose steps expressly identified. Moreover, the lettering of processsteps or ingredients is a convenient means for identifying discreteactivities or ingredients and the recited lettering can be arranged inany sequence, unless otherwise indicated.

The term “polyester,” as used herein, is intended to includehomopolyesters, copolyesters, and terpolyesters. In general, polyestersare synthetic polymers prepared by the polycondensation of one or moredifunctional carboxylic acids with one or more difunctional hydroxylcompounds. Typically, the difunctional carboxylic acid is a dicarboxylicacid or a hydroxycarboxylic acid, and the difunctional hydroxyl compoundis a dihydric alcohol such as, for example, glycols and diols. In thepresent invention, the difunctional carboxylic acid may be an aliphaticor cycloaliphatic dicarboxylic acid such as, for example, adipic acid,or an aromatic dicarboxylic acid such as, for example, terephthalicacid. The difunctional hydroxyl compound may be cycloaliphatic diol suchas, for example, 1,4-cyclohexanedimethanol, a linear or branchedaliphatic diol such as, for example, 1,4-butanediol, or an aromatic diolsuch as, for example, hydroquinone.

The term “polyamide,” as used herein, is intended to include syntheticpolymers prepared by the polycondensation of one or more difunctionalcarboxylic acids with one or more difunctional amines or by thering-opening polymerization of a lactam and may include homopolymers andcopolymers. For example, the difunctional carboxylic acid can be adicarboxylic acid such as adipic acid or isophthalic acid, and thedifunctional amines can be a diamine such as, for example, hexamethylenediamine or m-xylylenediamine. The term “copolyamide,” as used herein, isunderstood to mean a polyamide comprising at least 2, chemicallydistinct repeating units. For example, MXD6 nylon, is not a copolyamidebecause it contains only a single, chemically distinct repeating unitcontaining the residues of adipic acid and m-xylylenediamine. Bycontrast, poly(hexamethylene adipamide-co-isophthalamide), prepared bythe condensation of hexamethylenediamine with adipic and isophthalicacid, has two chemically distinct repeating units, that is, a repeatingunit containing the residues of hexamethylenediamine and adipic acid,and another repeating unit containing the residues of hexamethylenediamine and isophthalic acid.

The term “polycarbonate” is herein defined as the condensation productof a carbonate source and a diol source, having a carbonate componentcontaining 100 mole percent carbonate units and a diol componentcontaining 100 mole percent diol units, for a total of 200 mole percentmonomeric units or 100 mole percent “repeating units.” In one embodimentof the present invention, the polycarbonate portion of the firstcomponent is based upon the polycarbonate of4,4′-isopropylidenediphenol, commonly known as bisphenol Apolycarbonate. A wide variety of the linear or branched polycarbonatesthat may be utilized in the present invention may be derived frombisphenol A and can be prepared according to procedures well known inthe art such as, for example, as disclosed in U.S. Pat. Nos. 3,030,335and 3,317,466. Examples of bisphenol A polycarbonates that may be usedin the present invention and are available commercially include thematerials marketed under the tradenames LEXAN®, available from theGeneral Electric Company, and MAKROLON®, available from Bayer, Inc.

The term “polyarylate,” as used herein, is understood to mean polyestersprepared by the polycondensation of one or more difunctional aromaticdicarboxylic acids with one or more dihydric phenols. For example,typical aromatic dicarboxylic acids are terephthalic and isophthalicacid, and typical aromatic diphenols are bisphenol A and hydroquinone.

The term “residue,” as used herein in reference to the polymers of theinvention, means any organic structure incorporated into a polymerthrough a polycondensation or ring opening reaction involving thecorresponding monomer. The term “repeating unit,” as used herein, meansshortest sequence of monomer residues that can be found repeatedly in apolymer. For example, in polyesters, a repeating unit is an organicstructure having dicarboxylic acid residue and a diol residue, orhydroxycarboxylic acid residues bonded through a carbonyloxy group. In apolyamide, a repeating unit is an organic structure having adicarboxylic acid and a diamine residue, lactam, or aminoacid residues,bonded through a amide group.

It will also be understood by persons having ordinary skill in the art,that the residues associated within the various polyesters, polyamide,polycarbonates, and polyarylates of the invention can be derived fromthe parent monomer compound itself or any derivative of the parentcompound. For example, the dicarboxylic acid and amino acid residuesreferred to in the polymers of the invention may be derived from adicarboxylic acid or aminoacid monomer or its associated acid halides,esters, salts, anhydrides, or mixtures thereof. Thus, as used herein,the term “dicarboxylic acid” or “aminoacid” is intended to includedicarboxylic acids and any derivative of a dicarboxylic acid, includingits associated acid halides, esters, half-esters, salts, half-salts,anhydrides, mixed anhydrides, or mixtures thereof, useful in apolycondensation process with a diol to make a high molecular weightpolyester or polyamide. “Hydroxycarboxylic acid” is intended to includealiphatic and cycloaliphatic hydroxycarboxylic acids as well asmonohydroxy-monocarboxylic acids and any derivative thereof, includingtheir associated acid halides, esters, cyclic esters (including dimerssuch as lactic acid lactides), salts, anhydrides, mixed anhydrides, ormixtures thereof, useful in a polycondensation process or ring openingreaction to make a high molecular weight polyester. Similarly,“aminoacid” is intended to include aliphatic, aromatic, andcycloaliphatic aminoacids and any derivative thereof, including theirassociated acid halides, amides, cyclic amides (lactams), salts,anhydrides, mixed anhydrides, or mixtures thereof, useful in apolycondensation process or ring opening reaction to make a highmolecular weight polyamide. In addition, the term “diamine” is intendedto include diamines as well as their associated salts, amides, or anyother derivative thereof that are useful for the preparation ofpolyamides.

Whenever the term “inherent viscosity” (I.V.) is used in thisapplication, it will be understood to refer to viscosity determinationsmade at 25° C. using 0.5 grams of polymer per 100 ml of a solventcomprising 60 weight percent phenol and 40 weight % tetrachloroethane.

The term “refractive index” (abbreviated herein as “RI”) as used herein,refers to refractive index measurements obtained according to standardmethods well known in the art. The refractive indices reported hereinwere determined at a wavelength of 633 nm using a Metricon PrismCoupler™ model 2010 refractometer (available from Metricon Inc.) and arereported as the average of the refractive indices measured in 3orthogonal directions (extrusion or stretch, transverse, and thicknessdirections). The phrase “difference in refractive index” as used hereinin the context of the compositions, processes, and shaped articles ofthe invention always means the value obtained by subtracting therefractive index of the polyester, polycarbonate, orpolyarylate-containing component (typically referred to herein as the“first component” or “first layer” in multilayered articles) from therefractive index of the polyamide- or copolyamide-containing component(typically referred to herein as the “second component” or “secondlayer” in multilayered articles). Thus, in accordance with theinvention, the difference in refractive index (“ΔRI”) should becalculated according to the following formula:

ΔRI=RI(second component or layer)−RI(first component or layer)

It will be evident to persons skilled in the art that the difference inrefractive index may be a positive or negative number.

The term “% haze,” as used herein, refers to haze values determinedaccording to ASTM Method D1003 using a HunterLab UltraScan Sphere 8000Colorimeter manufactured by Hunter Associates Laboratory, Inc., Reston,Va. using Hunter's Universal Software (version 3.8) (% Haze=100*DiffuseTransmission/Total Transmission). The procedure for the determination ofrefractive index is provided in the Examples. For the compositions ofthe invention, haze and % transmittance are determined by molding orcasting the composition into a sheet or film having a thickness of ⅛inch or less and measuring the haze according to the procedure describedin the examples. For shaped articles, including multilayer shapedarticles, the haze and % transmittance can be determined by cutting outa small (i.e., 1×1 cm) section of the article, having a thickness of ⅛inch or less, and measuring the haze according the procedure describedherein.

The term glass transition temperature (“Tg”) as used herein, refers tothe Tg values determined using differential scanning calorimetry(“DSC”), typically using a scan rate of 20° C./min. An example of a DSCinstrument is TA Instruments 2920 Differential Scanning calorimeter.

The compositions of the present invention comprise a first componentcomprising one or more thermoplastic polymers selected from polyesters,polycarbonates, polyarylates, and homogeneous blends thereof. The term“thermoplastic polymer,” as used herein, is intended to have its plainmeaning as would be understood by persons having ordinary skill in theart, that is, a polymer that softens when exposed to heat and returns toits original condition when cooled to room temperature. The firstcomponent may comprise a single thermoplastic polymer or may comprise ablend of 2 or more polymers provided that the blend is a homogeneousblend. The term “homogeneous blend,” as used herein, is synonymous withthe term “miscible,” and is intended to mean that the blend has asingle, homogeneous phase as indicated by a single,composition-dependent Tg. For example, a first polymer that is misciblewith second polymer may be used to “plasticize” the second polymer asillustrated, for example, in U.S. Pat. No. 6,211,309. Homogeneous blendsmay be formed by simply blending two or polymers or, in the case ofcondensation polymers such as for example, polyesters or polyamides, bytransesterifying or transamidating two or more polymers. By contrast,the term “immiscible,” as used herein, denotes a blend that shows atleast 2, randomly mixed, phases and exhibits more than one Tg. Somepolymers may be immiscible and yet compatible with each other. A furthergeneral description of miscible and immiscible polymer blends and thevarious analytical techniques for their characterization may be found inPolymer Blends Volumes 1 and 2, Edited by D. R. Paul and C. B. Bucknall,2000, John Wiley & Sons, Inc.

The first component may comprise one or more thermoplastic polymersselected from polyesters, polycarbonates, polyarylates, and homogeneousblends thereof. For example, the first component may comprise apolyester comprising (a) diacid residues, comprising at least 80 molepercent, based on the total diacid residues, of the residues of at leastone dicarboxylic acid selected from terephthalic acid, isophthalic acid,naphthalenedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid, and0 to about 20 mole percent of the residues of at least one modifyingdicarboxylic acid having 2 to 20 carbon atoms; and (b) diol residuescomprising at least 80 mole percent, based on the total moles of diolresidues, of the residues of at least one diol selected from ethyleneglycol, 1,4-cyclohexanedimethanol; neopentyl glycol, diethylene glycol,1,3-propanediol, 1,4-butanediol, and,2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20 molepercent of the residues of at least one modifying diol having from 3 to16 carbons. Cyclic diols containing cis and trans isomers may be used asthe pure cis or trans isomer or as a mixture of cis and trans isomers.

For example, the diacid residues can comprise the residues of one ormore dicarboxylic acids selected from terephthalic acid, isophthalicacid, or combinations thereof, and the diol residues comprise theresidues of one or more diols selected from 1,4-cyclohexanedimethanol,neopentyl glycol, ethylene glycol, and combinations thereof. In oneembodiment, for example, the diacid residues may comprise the residuesof terephthalic acid and isophthalic acid. A higher concentration ofterephthalic acid in the polyester than isophthalic acid is advantageousbecause the resulting polyester provides greater impact strength to theblend. For example, the diacid residues may comprise from about 60 toabout 100 mole percent of the residues terephthalic acid and 0 to about40 mole percent of the residues isophthalic acid and the diol residuesmay comprise about 100 mole percent of the residues of1,4-cyclohexanedimethanol. Other examples of dicarboxylic acid contentinclude about 80 to about 100 mole percent terephthalic acid and 0 to 20mole percent isophthalic acid, and about 100 mole percent terephthalicacid.

Other representative polyesters that may be used as the thermoplasticpolymers of component (i) include polyesters comprising: (a) diacidresidues comprising 80 to 100 mole percent of the residues ofterephthalic acid and diol residues comprising about 50 to about 90 molepercent of the residues of 1,4-cyclohexanedimethanol and about 10 toabout 50 mole percent of the residues of neopentyl glycol; (b) diacidresidues comprising 100 mole percent of the residues of terephthalicacid and diol residues comprising about 10 to about 40 mole percent ofthe residues of 1,4-cyclohexanedimethanol and 60 to about 90 molepercent of the residues of ethylene glycol; (c) diacid residuescomprising 100 mole percent terephthalic acid and diol residuescomprising about 10 to about 99 mole percent of the residues of1,4-cyclohexanedimethanol, 0 to about 90 mole percent of the residues ofethylene glycol, and about 1 to about 25 mole percent of the residues ofdiethylene glycol; and (d) diacid residues comprising 100 mole percentterephthalic acid and diol residues comprising about 50 to about 90 molepercent 1,4-cyclohexanedimethanol and about 10 to about 50 mole percentethylene glycol.

In yet another example, the dicarboxylic acid may be selected fromterephthalic acid and isophthalic acid, and the diol is selected from1,4-cyclohexanedimethanol and ethylene glycol. In one composition, forexample, the dicarboxylic acid is terephthalic acid and the diol is1,4-cyclohexanedimethanol. In yet another example, the diacid residuesmay comprise at least 95 mole percent of the residues of terephthalicacid and the diol residues may comprise about 10 to about 40 molepercent of the residues of 1,4-cyclohexanedimethanol, about 1 to about25 mole percent of the residues of diethylene glycol, and about 35 toabout 89 mole percent of the residues of ethylene glycol.

The polyester may further comprise 0 to about 20 mole percent of one ormore residues of a modifying diacid containing 2 to 20 carbon atoms ifdesired. For example, from 0 to about 30 mole % of other aromaticdicarboxylic acids containing 8 to about 16 carbon atoms, cycloaliphaticdicarboxylic acids containing 8 to about 16 carbon atoms, aliphaticdicarboxylic acids containing about 2 to about 16 carbon atoms, ormixtures thereof may be used. Examples of modifying carboxylic acidsinclude, but are not limited to, one or more of4,4′-biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid,1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid,2,7-naphthalenedicarboxylic acid, 4,4′-oxybenzoic acid,trans-4,4′-stilbenedicarboxylic acid, oxalic acid, malonic acid,succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid,azelaic acid, and sebacic acid.

In another embodiment, the polyester can comprise about 1 to about 99mole percent, based on the total moles of diol residues, of the residuesof 1,4-cyclohexanedimethanol, about 99 to about 1 mole percent of theresidues ethylene glycol. Typical mole percentages for the residues of1,4-cyclohexanedimethanol for the polyesters of the invention includefrom about 1 to about 10 mole percent, from about 1 to about 25 molepercent, from about 1 to about 40 mole percent, 50 mole percent andgreater, and 100 mole percent. In another embodiment, for example, thedicarboxylic acid is 1,4-cyclohexanedicarboxylic acid and the diol is1,4-cyclohexanedimethanol. In a further example, the polyester maycomprise the residues of 1,4-cyclohexanedimethanol units and theneopentyl glycol. In yet another example, the polyester may comprise theresidues of 1,4-cyclohexanedimethanol units and2,2,4,4-tetramethyl-1,3-cyclobutanediol.

The diol component of the polyester also may be modified from 0 to about20 mole percent of the residues of at least one modifying diol havingfrom 3 to 16 carbons. Other ranges of modifying diol include, but arenot limited to, from 0 to about 10 mole percent, and less than 5 molepercent. The modifying diol may be selected from one or more of1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol,1,6-hexanediol, 1,4-cyclohexanedimethanol, p-xylene glycol, neopentylglycol, polyethylene glycol, polytetramethylene glycol, and2,2,4,4-tetramethyl-1,3-cyclobutanediol. Examples of polyalkyleneglycols include poly(tetramethylene glycol) (“PTMG”) and poly(ethyleneglycol) (“PEG”) having molecular weights up to about 2,000. The diolcomponent, for example, can be modified with 0 to about 10 mole percentpolyethylene glycol or polytetramethylene glycol to enhance elastomericbehavior. In another example, the diol residues may comprise about 10 toabout 99 mole percent of residues of 1,4-cyclohexanedimethanol, 0 toabout 90 mole percent of residues of ethylene glycol, and about 1 toabout 25 mole percent of residues of diethylene glycol. The polyesteralso may contain up to about 5 mole percent, typically from about 0.1 toabout 2.0 mole %, based on the acid or diol component, of the residuesof a polyfunctional branching agent derived from a compound having atleast three carboxyl and/or hydroxy groups to form a branched polyester.Examples of such compounds include trimellitic acid or anhydride,trimesic acid, pyromellitc anhydride, trimethylolethane,trimethylolpropane, a trimer acid, and the like. It will be understoodby persons skilled in the art that the final composition can be arrivedat by blending various resins or by direct reactor copolymerization. Thelatter is desirable to minimize compositional variability but economicnecessities often make blending more cost effective.

Additional examples of polyesters are those containing 100 mole percentterephthalic residues, based on the total diacid residues, and any oneof the following diol residue compositions, based on the total diolresidues: (i) about 1 to about 5 mole percent of the residues of1,4-cyclohexanedimethanol and about 99 to about 95 mole percent of theresidues of ethylene glycol; (ii) about 29 to about 33 mole percent ofthe residues of 1,4-cyclohexanedimethanol and about 71 to about 67 molepercent of the residues of ethylene glycol; (iii) about 45 to about 55mole percent of the residues of 1,4-cyclohexanedimethanol and about 55to about 45 mole percent of the residues of ethylene glycol; (iv) about60 to about 65 mole percent of the residues of 1,4-cyclohexanedimethanoland about 40 to about 35 mole percent of the residues of ethyleneglycol; (v) about 79 to about 83 mole percent of the residues of1,4-cyclohexanedimethanol and about 21 to about 17 mole percent of theresidues of ethylene glycol; and (vi) about 100 mole percent of theresidues of 1,4-cyclohexanedimethanol.

The polyesters generally will have inherent viscosity (I.V.) values inthe range of about 0.4 dL/g to about 1.4 dL/g. Additional examples ofI.V. ranges include about 0.65 dL/g to about 1.0 dL/g and about 0.7 dL/gto about 0.85 dL/g. As described previously, inherent viscosity ismeasured at 25° C. using 0.5 grams of polymer per 100 ml of a solventcomprising 60 weight percent phenol and 40 weight % tetrachloroethane

The polymers of the invention may be crystalline, semicrystalline, oramorphous polymers. The term “semicrystalline,” as used herein, meansthat the polymer contains two phases: an ordered crystalline phase andan unordered amorphous phase. Polymers with a semicrystalline morphologyexhibit both a crystalline melting temperature (Tm) and a glasstransition temperature (Tg) and may be distinguished from “amorphous”polymers, which exhibit only a glass transition temperature.

The polyesters used in the present invention typically are prepared fromdicarboxylic acids and diols which react in substantially equalproportions and are incorporated into the polyester polymer as theircorresponding residues. The polyesters derived from dicarboxylic acidand diol residues of the present invention, therefore, containsubstantially equal molar proportions of acid residues (100 molepercent) and diol residues (100 mole percent) such that the total molesof repeating units is equal to 100 mole percent. The mole percentagesprovided in the present disclosure, therefore, may be based on the totalmoles of acid residues, the total moles of diol residues, or the totalmoles of repeating units. For example, a copolyester containing 30 molepercent terephthalic acid, based on the total acid residues, means thatthe copolyester contains 30 mole percent terephthalic residues out of atotal of 100 mole percent acid residues. Thus, there are 30 moles ofterephthalic residues among every 100 moles of acid residues. In anotherexample, a copolyester containing 30 mole percent1,4-cyclohexanedimethanol, based on the total diol residues, means thatthe copolyester contains 30 mole percent 1,4-cyclohexanedimethanolresidues out of a total of 100 mole percent diol residues. Thus, thereare 30 moles of 1,4-cyclohexanedimethanol residues among every 100 molesof diol residues. As used herein, copolyesters of terephthalic acid,ethylene glycol, and 1,4-cyclohexandimethanol may be referred to as“PET” when the glycol component is primarily ethylene glycol, “PCT” whenthe glycol component is primarily 1,4-cyclohexanedimethanol, “PETG” whenthe ratio of ethylene glycol to 1,4-cyclohexanedimethanol is greaterthan 1 and “PCTG” when the ratio of ethylene glycol to1,4-cyclohexanedimethanol ratio is less than 1.

The polyesters of the instant invention are readily prepared from theappropriate dicarboxylic acids, esters, anhydrides, or salts, and theappropriate diol or diol mixtures using typical polycondensationreaction conditions. Thus, the dicarboxylic acid component of thepolyesters of the present invention can be derived from dicarboxylicacids, their corresponding esters, or mixtures thereof. Examples ofesters of the dicarboxylic acids useful in the present invention includethe dimethyl, dipropyl, diisopropyl, dibutyl, and diphenyl esters, andthe like.

The polyesters of the present invention are prepared by procedures knownto persons skilled in the art. They may be made by continuous,semi-continuous, and batch modes of operation and may utilize a varietyof reactor types. Examples of suitable reactor types include, but arenot limited to, stirred tank, continuous stirred tank, slurry, tubular,wiped-film, falling film, or extrusion reactors. The reaction of thediol and dicarboxylic acid may be carried out using conventionalpolyester polymerization conditions or by melt phase processes, butthose with sufficient crystallinity may be made by melt phase followedby solid phase polycondensation techniques. For example, when preparingthe polyester by means of an ester interchange reaction, i.e., from theester form of the dicarboxylic acid components, the reaction process maycomprise two steps. In the first step, the diol component and thedicarboxylic acid component, such as, for example, dimethylterephthalate, are reacted at elevated temperatures, typically, about150° C. to about 250° C. for about 0.5 to about 8 hours at pressuresranging from about 0.0 kPa gauge to about 414 kPa gauge (60 pounds persquare inch, “psig”). Preferably, the temperature for the esterinterchange reaction ranges from about 180° C. to about 230° C. forabout 1 to about 4 hours while the preferred pressure ranges from about103 kPa gauge (15 psig) to about 276 kPa gauge (40 psig). Thereafter,the reaction product is heated under higher temperatures and underreduced pressure to form the polyester with the elimination of diol,which is readily volatilized under these conditions and removed from thesystem. This second step, or polycondensation step, is continued underhigher vacuum and a temperature which generally ranges from about 230°C. to about 350° C., preferably about 250° C. to about 310° C. and, mostpreferably, about 260° C. to about 290° C. for about 0.1 to about 6hours, or preferably, for about 0.2 to about 2 hours, until a polymerhaving the desired degree of polymerization, as determined by inherentviscosity, is obtained. The polycondensation step may be conducted underreduced pressure which ranges from about 53 kPa (400 torr) to about0.013 kPa (0.1 torr). Stirring or appropriate conditions are used inboth stages to ensure adequate heat transfer and surface renewal of thereaction mixture. The reaction rates of both stages are increased byappropriate catalysts such as, for example, alkoxy titanium compounds,alkali metal hydroxides and alcoholates, salts of organic carboxylicacids, alkyl tin compounds, metal oxides, and the like. A three-stagemanufacturing procedure, similar to that described in U.S. Pat. No.5,290,631, may also be used, particularly when a mixed monomer feed ofacids and esters is employed.

To ensure that the reaction of the diol component and dicarboxylic acidcomponent by an ester interchange reaction is driven to completion, itis sometimes desirable to employ about 1.05 to about 2.5 moles of diolcomponent to one mole dicarboxylic acid component. Persons of skill inthe art will understand, however, that the ratio of diol component todicarboxylic acid component is generally determined by the design of thereactor in which the reaction process occurs.

In the preparation of polyester by direct esterification, i.e., from theacid form of the dicarboxylic acid component, polyesters are produced byreacting the dicarboxylic acid or a mixture of dicarboxylic acids withthe diol component or a mixture of diol components. The reaction isconducted at a pressure of from about 7 kPa gauge (1 psig) to about 1379kPa gauge (200 psig), preferably less than 689 kPa (100 psig) to producea low molecular weight polyester product having an average degree ofpolymerization of from about 1.4 to about 10. The temperatures employedduring the direct esterification reaction typically range from about180° C. to about 280° C., more preferably ranging from about 220° C. toabout 270° C. This low molecular weight polymer may then be polymerizedby a polycondensation reaction.

The thermoplastic polymers of the invention may also comprise apolyarylate. Polyarylates are obtained by polymerization of a dihydricphenol and a dicarboxylic acid. Examples of polyarylates that can beused in the compositions, processes, and shaped articles of the instantinvention are described in U.S. Pat. Nos. 4,598,130; 5,034,502; and4,374,239. Examples of dihydric phenols that can be used to prepare thepolyarylates are bisphenols such as bis(4-hydroxyphenyl)methane;2,2-bis(4-hydroxyphenyl) propane (“bisphenol-A”);2,2-bis(4-hydroxy-3-methylphenyl)propane;4,4-bis(4-hydroxyphenyl)heptane;2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane;2,2-bis(4-hydroxy-3,5-dibromophenyl)propane; dihydric phenol ethers suchas, for example, bis(4-hydroxyphenyl)ether;bis(3,5-dichloro-4-hydroxyphenyl)ether; dihydroxydiphenyls such as, forexample, p,p′-dihydroxydiphenyl, 3,3′-dichloro-4,4′-dihydroxydiphenyl;dihydroxyaryl sulfones such as, for example,bis(4-hydroxyphenyl)sulfone; bis(3,5-dimethyl-4-hydroxyphenyl)sulfone;dihydroxy benzenes such as, for example, resorcinol; hydroquinone; halo-and alkyl-substituted dihydroxy benzenes such as, for example,1,4-dihydroxy-2,5-dichlorobenzene; 1,4-dihydroxy-3-methylbenzene; anddihydroxy diphenyl sulfoxides such as, for example,bis(4-hydroxyphenyl)sulfoxide; and bis(3,5-dibromo-4-hydroxyphenyl)sulfoxide. A variety of additional dihydric phenols are also availablesuch as are disclosed, for example, in U.S. Pat. Nos. 2,999,835;3,028,365 and 3,153,008. Also suitable are copolymers prepared from theabove dihydric phenols copolymerized with halogen-containing dihydricphenols such as 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane and2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane. It is also possible toemploy two or more different dihydric phenols or a copolymer of adihydric phenol with a glycol, with hydroxy or acid terminatedpolyester, or with a dibasic acid as well as blends of any of the abovematerials. Suitable dicarboxylic acids include, but are not limited to,aromatic dicarboxylic acids such as phthalic, isophthalic, terephthalic,o-phthalic, o-, m-, and p-phenylenediacetic acids, and polynucleararomatic acids such as, for example, diphenic acid and 1,4-naphthalicacid.

Additional examples of polyarylates that can be used in the presentinvention include those polymers resulting from the polymerization ofbisphenol A (2,2-bis-(4-hydroxyphenyl)propane) and a 50:50 mixtureiso/terephthalic acids. Some of the polymers are commercially availableunder the trademark “U-Polymer U-100” (available from Unitika AmericaCorporation). Other examples are polyarylates based on tetramethylbisphenol-A; 4,4′-dihydroxy-benzophenone; and 5-tertiary-butylisophthalic acid dichloride.

The polyarylates of the present invention can be prepared by anypolyester forming reactions well known in the art such as, for example,interfacial polymerization by mixing a solution of an aromaticdicarboxylic acid dihalide in an organic solvent with an alkalineaqueous solution of a bisphenol under stirring to react these materials;solution polymerization by reacting an aromatic dicarboxylic aciddihalide with a bisphenol in the presence of a deacidifying agent suchas pyridine in an organic solvent; molten polymerization by reacting anaromatic dicarboxylic acid diphenyl ester with a bisphenol; moltenpolymerization by reacting an aromatic dicarboxylic acid, diphenylcarbonate and a bisphenol; molten polymerization by reacting an aromaticdicarboxylic acid with a bisphenol diacetate; and polymerization byreacting an aromatic dicarboxylic acid with a bisphenol diacetate.Examples of methods for preparation of polyarylates are disclosed inU.S. Pat. Nos. 5,034,502, 4,321,355, and 4,374,239. The polyarylates ofthe invention typically have inherent viscosities of about 0.5 to about1.1 dL/gm.

In addition, the polyester, polycarbonates, and polyarylates may furthercomprise one or more of the following: antioxidants, melt strengthenhancers, branching agents (e.g., glycerol, trimellitic acid andanhydride), chain extenders, flame retardants, fillers, acid scavengers,dyes, colorants, pigments, antiblocking agents, flow enhancers, impactmodifiers, antistatic agents, processing aids, mold release additives,plasticizers, slips, stabilizers, waxes, UV absorbers, opticalbrighteners, lubricants, pinning additives, foaming agents, antistats,nucleators, and the like. Colorants, sometimes referred to as toners,may be added to impart a desired neutral hue and/or brightness to thepolyester. Preferably, the polyester compositions may comprise 0 toabout 30 weight percent of one or more processing aids to alter thesurface properties of the composition and/or to enhance flow.Representative examples of processing aids include calcium carbonate,talc, clay, mica, zeolites, wollastonite, kaolin, diatomaceous earth,TiO₂, NH4Cl, silica, calcium oxide, sodium sulfate, and calciumphosphate. Use of titanium dioxide and other pigments or dyes, might beincluded, for example, to control whiteness of the film, or to make acolored articles. An antistat or other coating may also be applied tothe surface of the article.

The second component (ii) of the compositions of the invention comprisesa transamidized, homogeneous blend of at least two polyamides.Typically, the homogeneous blend will comprise from 2 to about 10different polyamides. In another example, the homogeneous blend cancomprise from 2 to 4 polyamides. In accordance with the presentinvention, polyamides that display a melting point below about 300° C.can be used as at least one polyamide. In another example, polyamideswith the melting point less than about 275° C. and glass transitiontemperature greater than about 25° C. may be used. Typically, thepolyamides have an I.V. between about 0.3 dL/g and about 2.0 dL/g and,preferably at least 0.5 dL/g.

For the composition of the invention, it is advantageous thattransamidation occur between the polyamides to produce of homogeneousblend. The term “transamidized,” as used herein, is intended to besynonymous with the terms “transamidate” and “transamidation,” and meansthe process of exchanging amido groups between two different polyamides.Transamidation between two or more polyamides can be accomplished bycontacting the polyamides at elevated temperatures, typically from about270° C. to about 350° C. Other examples of transamidation temperaturesare about 280° C. to about 350° C. and about 290° C. to about 340° C.Transamidation between the polyamides is indicated by the presence of asingle glass transition temperature (“Tg”) for the blend as determinedby differential scanning calorimetry (“DSC”) using standard techniqueswell known to persons skilled in the art such as, for example, describedin ASTM Method D3418. The polyamides may be heated together directly atthese temperature or in the presence of the thermoplastic polymers ofthe first component (i). For example, the contacting and, hence,transamidation of the polyamides can take place by melt blending of thefirst and second components, during extrusion, or other high temperatureprocessing of the polymer composition and its components. In anotherexample, the polyamides may be heated together in a separate vessel andthen melt blended with the first component.

The first and second polyamides of the second component may be selectedfrom a wide range of polyamides. To better match the refractive index ofthe first component, it is desirable, but not essential, that at leastone of the polyamides comprise aromatic residues. In one example, thepolyamides can comprise partially aromatic polyamides and aliphaticpolyamides having a number average molecular weight of 7,000 or less.Combinations of such polyamides are included also within the scope ofthe invention. Partially aromatic polyamides comprise amide linkagesbetween at least one aromatic ring and at least one nonaromatic species.Although wholly aromatic polyamides generally are liquid crystalline,the blends of such resins having melting points less than 300° C. can beused for this invention. When homogeneous blends of polyamides are used,the rapid transamidization (amide-amide interchange) of aliphatic nylonwith aromatic or partially aromatic polyamide permits the tailoring ofrefractive index of the polyamide blend by adjusting the ratios ofaliphatic polyamide to aromatic, or partially aromatic, polyamide. Thistechnique enables a matching of the refractive index of the homogeneouspolyamide blend to the thermoplastic polymer such as, for example, oneor more polyesters, of the first component. A reference fortransamidization can be found in the work by Y. Takeda, et. al.,Polymer, 1992 vol. 33, pg. 3394.

In accordance with the invention, the second component can be atransamidized, homogeneous blend of 2 or more polyamides such as, forexample, a first polyamide and a second polyamide which are selected togive a refractive index in the second component such that second andfirst components have a difference in refractive index (RI(secondcomponent)−RI(first component)) of about 0.006 to about −0.0006. Tomatch the refractive index of the first component, it is advantageousthat the first and second polyamide have different amounts of aromaticand aliphatic residues. For example, the second component (ii) cancomprise a homogeneous blend of a first polyamide, comprising aromaticresidues, and of a second polyamide comprising aliphatic residues. Theterm “aliphatic,” as used herein with respect to the diamine anddicarboxylic acid monomers of the polyamides of the present invention,means that carboxyl or amino groups of the monomer are not connectedthrough an aromatic nucleus. For example, adipic acid contains noaromatic nucleus in its backbone, i.e., the chain of carbon atomsconnecting the carboxylic acid groups; thus, it is “aliphatic.” Bycontrast, the term “aromatic” means the dicarboxylic acid or diaminecontains an aromatic nucleus in the backbone such as, for example,terephthalic acid or 1,4-metaxylylenediamine. Representative examples ofaromatic polyamides are those polyamides comprising at least 70 mole %of residues comprising diamines such as m-xylylenediamine or axylylenediamine mixture comprising m-xylylenediamine and up to 30% ofp-xylylenediamine and an aliphatic dicarboxylic acid having 6 to 10carbon atoms. The term “aliphatic,” therefore, is intended to includeboth aliphatic and cycloaliphatic structures such as, for example,diamine, diacids, lactams, aminoalcohols, and aminocarboxylic acids,that contain as a backbone a straight or branched chain or cyclicarrangement of the constituent carbon atoms which may be saturated orparaffinic in nature, unsaturated (i.e., containing non-aromaticcarbon-carbon double bonds), or acetylenic (i.e., containingcarbon-carbon triple bonds). Thus, in the context of the description andthe claims of the present invention, aliphatic is intended to includelinear and branched, chain structures (referred to herein as“aliphatic”) and cyclic structures (referred to herein as “alicyclic” or“cycloaliphatic”). The term “aliphatic,” however, is not intended toexclude any aromatic substituents that may be attached to the backboneof an aliphatic or cycloaliphatic diol or diacid or hydroxycarboxylicacid.

The weight percentage ratio of the first and second polyamides presentin the transamidized, homogeneous blend may range from about 1:50 toabout 50:1 based on the total weight of the second component. Otherexamples of weight percentage ratios are 1:20 to about 20:1 and about1:10 to about 10:1.

Examples of polyamides that may be used in the homogeneous blends of thepresent invention include polyamides comprising one or more of residuesselected from isophthalic acid, terephthalic acid,cyclohexanedicarboxylic acid, meta-xylylenediamine (also referred toherein as “m-xylylenediamine”), para-xylylenediamine (also referred toherein as “p-xylylenediamine”), 1,3-cyclohexane(bis)methylamine,1,4-cyclohexane(bis)-methylamine, aliphatic diacids with 6 to 12 carbonatoms, aliphatic amino acids or lactams with 6 to 12 carbon atoms,aliphatic diamines with 4 to 12 carbon atoms. Other generally knownpolyamide forming diacids and diamines can be used. The polyamides alsomay contain small amounts of trifunctional or tetrafunctional comonomerssuch as trimellitic anhydride, pyromellitic dianhydride, or otherpolyamide forming polyacids and polyamines known in the art.

Examples of partially aromatic polyamides include, but are not limitedto: poly(m-xylylene adipamide) (referred to herein as “MXD6” nylon),poly(hexamethylene isophthalamide), poly(hexamethyleneadipamide-co-isophthalamide), poly(hexamethyleneadipamide-co-terephthalamide), and poly(hexamethyleneisophthalamide-co-terephthalamide). In one embodiment, the partiallyaromatic polyamide is poly(m-xylylene adipamide). In one embodiment, thepartially aromatic polyamides may have a number average molecular weightof 7000 or less. Representative examples of aliphatic polyamides includepoly(2-pyrrolidinone) (nylon 4, 6; CAS No. 44, 299-2); polycapramide(nylon 6; CAS No. 18, 111-0), poly(2-piperidone) (nylon 5, CAS No.24938-57-6); poly(7-aminoheptanoic acid) (nylon 7; CAS No. 25035-01-2);poly(nonanamide) (nylon 9; CAS No. 25748-72-5); poly(11-aminoundecanoicacid) (nylon 11; CAS No. 25035-04-5); poly(12-aminol auric acid) (nylon12, CAS No. 24937-16-4); poly(ethyleneadipamide) (nylon 2,6);polytetramethylene-adipamide (nylon 4,6; CAS No. 50327-22-5);polyhexamethylene-adipamide (nylon 6,6; CAS No. 42, 917-1), (nylon 6,9;CAS No. 18, 806-9) poly-(hexamethylene-sebacamide) (nylon 6,10; CAS No.9008-66-6), poly(hexamethylene-undecanamide) (nylon 6, 11)poly(hexamethylene-dodecamide) (nylon 6,12; CAS No. 24936-74-1),poly(octamethylene-adipamide) (nylon 8,6); adipicacid-decamethylenediamine copolymer (nylon 10,6; CAS No. 26123-27-3);polydecamethylene-dodecamide (nylon 10, 12);poly(dodecamethylene-adipamide) (nylon 12,6); andpoly(dodecamethylene-sebacamide) (nylon 12,8).

For example, the second component (ii) can comprise a homogeneous blendcomprising a first polyamide comprising the residues ofm-xylylenediamine and adipic acid, and a second polyamide comprising theresidues of at least one aliphatic or cycloaliphatic monomer selectedfrom adipic acid, pimelic acid, suberic acid, azelaic acid, sebacicacid, undecanedioc acid, dodecanedioc acid, caprolactam, butyrolactam,11-aminoundecanedioc acid, isophthalic acid, and hexamethylene diamine.The first polyamide, for example, can comprise MXD6 nylon, which iscommercially available from Mitsubishi Corporation. In another example,the second polyamide can comprise at least one polyamide selected fromnylon 4; nylon 6; nylon 9; nylon 11; nylon 12; nylon 6,6; nylon 5,10;nylon 6,12; nylon 6,11; nylon 10,12; and combinations thereof. In yetanother example, the second polyamide can comprise nylon 6, nylon 6,6,or blends thereof.

The second component also may comprise a single copolyamide in which thecomposition of monomer residues is chosen to give a refractive indexthat closely matches the refractive index of the first component. Thus,in another embodiment, the invention provides a polymer composition,comprising an immiscible blend of:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a copolyamide;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less. For example, the copolyamide can the residues of    m-xylylenediamine, p-xylylenediamine, or a combination thereof; and    the residues of at least one monomer selected from terephthalic    acid, isophthalic acid, adipic acid, pimelic acid, suberic acid,    azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid,    caprolactam, butyrolactam, 11-amino-undecanedioc acid, and    1,6-hexamethylenediamine. In another example, the copolyamide can    comprise about 15 to about 100 mole percent of the residues of    m-xylylenediamine, based on a total diamine residue content of 100    mole %, and about 15 to about 85 mole percent of the residues adipic    acid and about 85 to about 15 mole percent of the residues of one or    more aliphatic or cycloaliphatic dicarboxylic acids selected from    pimelic acid, suberic acid, azelaic acid, sebacic acid, undecandioic    acid, dodecandioic acid, and 1,4-cyclohexanedicarboxylic acid, based    on a total diacid residue content of 100 mole %. It is understood    that the various embodiments of homogeneous blends of polyamides and    copolyamides referred to herein can be combined with any of the    embodiments of the polyesters discussed hereinabove.

Other examples of copolyamides that can be used as in composition of theinvention, either alone or as part of a homogeneous blend with anotherpolyamide, include, but are not limited to, copolyamides comprising fromabout 15 to about 100 mole percent of the residues of m-xylylenediamine,based on a total diamine residue content of 100 mole %, and the residuesof adipic acid. Typical amounts of adipic acid residues which may bepresent in these copolyamides, based on the total moles of diacidresidues, are about 5 to about 85 mole percent, about 20 to about 80mole percent, and about 25 to about 75 mole percent. The remainder ofthe dicarboxylic acid residues can comprise residues from one or morealiphatic dicarboxylic acids having from 7-12 carbon atoms, such aspimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioicacid, dodecanedioic acid, or 1,4-cyclohexanedicarboxylic acid. Inanother example, the polyamide acid also may comprise residues fromisophthalic acid and terephthalic acid.

The copolyamides of the invention also may comprise other diamines orlactam residues in addition to m-xylylenediamine residues. For example,the copolyamide can comprise at least 15 mole percent, or at least about20 mole percent of the residues of m-xylylenediamine with the remainderof the diamines residues comprising the residues of one or morealiphatic or aromatic diamines. For example, the copolyamide maycomprise about 80 mole percent or about 85 mole %, of the residues of1,6-hexamethylene diamine, based on the total moles of diamine residues.Varying amounts of p-xylylenediamine, 1,3-cyclohexanebis(methylamine),or 1,4-cyclohexanebis(methylamine), also may be used. Similarly, thecopolyamide may comprise the residues of a lactam, such as caprolactam,or lactams based on gamma-amino-butyric acid or 11-amino-undecanoicacid, in an amount from about 10 mole percent to about 90 mole percent,or from about 10 mole percent to about 70 mole percent based on thetotal moles of repeating units. In another embodiment, the copolyamidesof the invention can comprise from about 15 mole percent to about 85mole percent, about 20 to about 80 mole percent, or about 25 to about 75mole percent of the residues from m-xylylenediamine, based on the totalmoles of diamine residues with the remainder of the diamine residuescontent comprising residues from one or more diamines, such as aliphaticdiamines, and especially 1,6-hexamethylene diamine. In this embodiment,the diamine residues may further comprise minor amounts of the residuesof other diamines, for example p-xylylenediamine, or a cyclic aliphaticdiamine such as, for example, one or more of:1,3-cyclohexanebis(methylamine) or 1,4-cyclohexanebis(methylamine).Further, the polyamide may optionally include, in place of a portion ofthe adipic acid, residues from one or more aliphatic or aromaticdicarboxylic acids having from 7-12 carbon atoms, such as pimelic acid,suberic acid, azelaic acid, sebacic acid, undecandioic acid,dodecandioic acid, 1,4-cyclohexanedicarboxylic acid, or isophthalicacid, which may be present in an amount from about 15 mole percent toabout 85 mole percent, optionally with minor amounts of terephthalicacid. The polyamide also may comprise the residues of a lactam, such ascaprolactam, or lactams based on gamma-amino-butyric acid or11-amino-undecanoic acid, in an amount from about 10 mole percent toabout 90 mole percent, or about 10 mole % to 70 mole percent, based onthe total moles repeating units.

In yet another embodiment, the copolyamides according to the inventionmay comprise from about 15 mole percent up to about 90 mole percent ofresidues from adipic acid, with the remaining diacid residues comprisingthe about 10 to about 85 mole percent of the residues of isophthalicacid, based on the total moles of dicarboxylic acid residues. Additionalexamples of adipic acid and isophthalic acid residue content includeabout 20 to 80 mole percent, and about 25 to about 75 mole percent. Inthis embodiment, the polyamide may optionally comprise minor amounts ofresidues from one or more aliphatic dicarboxylic acids having from 7-12carbon atoms, such as pimelic acid, suberic acid, azelaic acid, sebacicacid, undecandioic acid, dodecandioic acid, or1,4-cyclohexanedicarboxylic acid, optionally with minor amounts ofterephthalic acid. Optionally, the polyamides may comprisem-xylylenediamine residues. Examples of m-xylylenediame residueconcentrations include about 15 to about 90 mole percent, about 20 toabout 85 mole percent, or about 25 to about 80 mole percent. Theremaining residues can comprise from one or more aliphatic diamines,such as, for example, 1,6-hexamethylene diamine, one or more aromaticdiamines such as, for example, p-xylylenediamine. Similarly, thecopolyamide also may comprise the residues of a lactam such as, forexample, caprolactam, or lactams based on gamma-amino-butyric acid or11-amino-undecanoic acid, in an amount from about 10 mole percent toabout 90 mole percent or about 10 mole percent to about 70 mole percent,based on the total moles of repeating units.

In yet another example, the copolyamides of the invention may comprisethe residues of one or more lactams such as, for example, caprolactam,or lactams based on gamma-amino-butyric acid or 11-amino-undecanoicacid, in an amount from about 10 mole percent to about 90 mole percent,or from about 10 mole percent to about 70 mole percent, or from about 15mole percent to about 60 mole percent, based on the total moles ofrepeating units. The residues of one or more aliphatic dicarboxylicacids having from 7-12 carbon atoms, such as pimelic acid, suberic acid,azelaic acid, sebacic acid, undecandioic acid, dodecandioic acid, or1,4-cyclohexanedicarboxylic acid, also may be present in amounts fromabout 20 mole percent to about 80 mole percent, based on the total molesof repeating units. For example, the copolyamide may comprise residuesfrom isophthalic acid or terephthalic acid. In this embodiment, thecopolyamides can comprise from about 15 mole percent to about 85 molepercent of the residues from m-xylylenediamine, based on the total molesof diamine residues. Other examples of m-xylylenediamine content areabout 20 to about 80 mole percent and about 25 to about 75 mole percent.The remainder of the diamine residues may comprise the residues of oneor more diamines aliphatic diamines such as, for example,1,6-hexamethylene diamine. In this embodiment, the diamine residues mayfurther comprise minor amounts of the residues of other diamines, forexample p-xylylenediamine, or a cyclic aliphatic diamine such as, forexample, one or more of: 1,3-cyclohexanebis(methylamine) or1,4-cyclohexanebis(methylamine). Optionally, minor amounts of one ormore of: p-xylylenediamine, 1,3-cyclohexanebis(methylamine), or1,4-cyclohexane-bis(methylamine), may be used.

Another embodiment of the invention is polymer composition, consistingessentially of an immiscible blend of:

-   (i) a first component consisting essentially of at least one    thermoplastic polymer selected from polyesters, polycarbonates,    polyarylates, and homogeneous blends thereof; and-   (ii) a second component consisting essentially of a homogeneous,    transamidized blend of at least 2 polyamides;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less. The phrase “consisting essentially of,” as used herein is    intended to encompass compositions which are immiscible blends, that    is, having at least 2, composition-dependent Tg's as measured by    DSC, and which have first component containing a polyester,    polycarbonate, polyarylate, or homogeneous blends thereof and a    second component containing a homogeneous, transamidized blend of at    least 2 polyamides. In this embodiment, the composition is    understood to exclude any elements that would substantially alter    the essential properties of the composition to which the phrase    refers. For example, compositions may include other components that    do not alter the refractive index of the components, % haze of the    blend, the % transmittance, or the miscibility of the blend. For    example, the addition of a compatibilizer, which may alter the    miscibility and refractive index of the composition, would be    excluded from this embodiment. Similarly, a second component    containing a copolyamide prepared by copolymerization of the    component monomers would be excluded because such a copolyamide    would be considered to have different properties than a homogeneous,    transamidized blend of at least 2 polyamides, even if the mole    percentage of the monomer residues are equivalent.

Similarly, another embodiment of the instant invention is anoxygen-scavenging composition consisting essentially of:

-   (A) an immiscible blend consisting essentially of    -   (i) first component consisting essentially of at least one        thermoplastic polymer selected from polyester, polycarbonate,        polyarylate, and homogeneous blends thereof;    -   (ii) a second component consisting essentially of a copolyamide        or a transamidized, homogeneous blend of at least two        polyamides;    -   wherein the second component (ii) and the first component (i)        have a difference in refractive index, RI(second        component)−RI(first component), of about 0.006 to about −0.0006,        and the immiscible blend has a percent transmittance of at least        75%, and a haze of 10% or less; and-   (B) at least one metal selected from Groups 3-12, Rows 4-6 of the    Periodic Table of the Elements.

In this embodiment, the composition is understood to exclude anyelements that would substantially alter the essential properties of thecomposition to which the phrase refers, such as, for example, therefractive index of the components, % haze of the blend, the %transmittance, the miscibility of the blend, or the oxygen-scavengingproportions of the composition. For example, the addition anoxygen-scavenging component other than a copolyamide or a transamidizedblend of polyamides such as, for example, a diene, polyether, or anyeasily oxidizable organic compound other than the components as listedin the claims would be excluded.

The polyamides used in the present invention typically are prepared fromdicarboxylic acids and diamines, which react in substantially equalproportions, or by the ring-opening polymerization of lactams, and areincorporated into the polyamide polymer as their corresponding residues.The polyamides derived from dicarboxylic acid and diamine residues ofthe present invention, therefore, contain substantially equal molarproportions of acid residues (100 mole percent) and diamine residues(100 mole percent) such that the total moles of repeating units is equalto 100 mole percent. The mole percentages provided in the presentdisclosure, therefore, may be based on the total moles of acid residues,the total moles of diamine residues, or the total moles of repeatingunits. For example, a polyamide or copolyamide containing 30 molepercent terephthalic acid, based on the total acid residues, means thatthe copolyamide contains 30 mole percent terephthalic residues out of atotal of 100 mole percent acid residues. Thus, there are 30 moles ofterephthalic residues among every 100 moles of acid residues. In anotherexample, a copolyamide containing 30 mole percent m-xylylenediamine,based on the total diamine residues, means that the copolyester contains30 mole percent m-xylylenediamine residues out of a total of 100 molepercent diamine residues. Thus, there are 30 moles of m-xylylenediamineresidues among every 100 moles of diamine residues.

Any method known in the art can be used to produce the polyamides. Thepolyamides are generally prepared by melt phase polymerization from adiacid-diamine complex which may be prepared either in situ or in aseparate step. In either method, the diacid and diamine are used asstarting materials. Alternatively, an ester form of the diacid may beused, preferably the dimethyl ester. If the ester is used, the reactionmust be carried out at a relatively low temperature, generally 80 to120° C., until the ester is converted to an amide. The mixture is thenheated to the polymerization temperature. In the case ofpolycaprolactam, either caprolactam or 6-aminocaproic acid can be usedas a starting material and the polymerization may be catalyzed by theaddition of adipic acid/hexamethylene diamine salt which results in anylon 6/66 copolymer. When the diacid-diamine complex is used, themixture is heated to melting and stirred until equilibration.

The molecular weight is controlled by the diacid-diamine ratio. Anexcess of diamine produces a higher concentration of terminal aminogroups. For oxygen-scavenging compositions, it is advantageous to adjustthe diacid-diamine ratio to produce the concentration of terminal aminegroups to 20 mmole/kg or less. If the diacid-diamine complex is preparedin a separate step, excess diamine is added prior to the polymerization.The polymerization can be carried out either at atmospheric pressure orat elevated pressures.

To exhibit satisfactory clarity and low haze, the second component andfirst component of the immiscible blend typically have refractiveindices which differ by about 0.006 to about −0.0006, that is, theRI(second component)−RI(first component) is about 0.006 to about−0.0006. Other examples of differences in the absolute value of therefractive indices are about 0.005 to about −0.0006, about 0.004 toabout −0.0006, about 0.003 to about −0.0006, about 0.005 to about−0.0005, and about 0.004 to about −0.0005. Persons of skill in the artwill understand, however, that the difference in refractive indiceswhich may be acceptable depends on the blend composition, particlediameter, refractive index, wavelength, and particle structure asdescribed by Biangardi et al., Die Angew. Makromole. Chemie, 183, 221(1990).

The immiscible blend of the instant invention has excellent clarity andhas a % transmittance of at least 75%, as determined by ASTM MethodD1003, and a haze of 10% or less. Other examples of % transmittance areat least 77%, at least 80%, and at least 85%. Additional examples ofhaze values which may be exhibited by the blends of the invention are 9%or less, 7% or less, 5% or less, and 3% or less. For the compositions ofthe invention, haze is determined by molding or casting the compositioninto a sheet or film having a thickness of ⅛ inch or less and measuringthe haze according to the procedure described in the examples. Forshaped articles, including multilayer shaped articles, the haze can bedetermined by cutting out a small (i.e., 1×1 cm) section of the article,having a thickness of ⅛ inch or less, and measuring the haze accordingthe procedure given in the examples.

The first component also may comprise homogeneous blend of one or morepolymers. For example, the first component may comprise a homogeneousblend of a first polyester with one or more polymers chosen from apolycarbonate, a second polyester, and a polyarylate. The polyester maybe any polyester as described herein. For example, the first componentmay comprise a homogeneous blend of a polyester and a polycarbonatecomprising the residues of bisphenol A.

The polycarbonate may comprise about 90 to 100 mole percent, based onthe total moles of diol residues, of the residues bisphenol A, and from0 to about 10 mole percent of the residues of one or more modifyingaliphatic diols or dihydric phenols having from 2 to 16 carbons.Representative examples include bis(4-hydroxyphenyl)methane;2,2-bis(4-hydroxyphenyl)propane (“bisphenol-A”);2,2-bis(4-hydroxy-3-methylphenyl)propane;4,4-bis(4-hydroxyphenyl)heptane;2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane;2,2-bis(4-hydroxy-3,5-dibromophenyl)propane; dihydric phenol ethers suchas, for example, bis(4-hydroxyphenyl)ether;bis(3,5-dichloro-4-hydroxyphenyl)ether; dihydroxydiphenyls such as, forexample, p,p′-dihydroxydiphenyl, 3,3′-dichloro-4,4′-dihydroxydiphenyl;dihydroxyaryl sulfones such as, for example,bis(4-hydroxyphenyl)sulfone; bis(3,5-dimethyl-4-hydroxyphenyl)sulfone;dihydroxy benzenes such as, for example, resorcinol; hydroquinone; halo-and alkyl-substituted dihydroxy benzenes such as, for example,1,4-dihydroxy-2,5-dichlorobenzene; 1,4-dihydroxy-3-methylbenzene; anddihydroxy diphenyl sulfoxides such as, for example,bis(4-hydroxyphenyl)sulfoxide; andbis(3,5-dibromo-4-hydroxyphenyl)sulfoxide. A variety of additionaldihydric phenols are also available such as are disclosed, for example,in U.S. Pat. Nos. 2,999,835; 3,028,365 and 3,153,008. Also suitable arecopolymers prepared from the above dihydric phenols copolymerized withhalogen-containing dihydric phenols such as2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane and2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane. It is also possible toemploy two or more different dihydric phenols or a copolymer of adihydric phenol with a glycol, with hydroxy or acid terminatedpolyester, or with a dibasic acid as well as blends of any of the abovematerials. Suitable dicarboxylic acids include, but are not limited to,aromatic dicarboxylic acids such as phthalic, isophthalic, terephthalic,o-phthalic, o-, m-, and p-phenylenediacetic acids, and polynucleararomatic acids such as, for example, diphenic acid and 1,4-naphthalicacid.

Representative examples of aliphatic diols include ethylene glycol,propanediols, butanediols, pentanediols, hexandiols, heptanediols,octanediols, neopentyl glycol, aryl-alkyl glycols such as styreneglycol, xylylene glycols, dihydroxy alkyl ethers of dihydric phenolssuch as the dihydroxy ethyl ether of Bisphenol-A, and the like. Otherexamples of aliphatic diols are higher molecular weight aliphaticdihydroxy compounds such as, for example, polyethylene glycols,polystyrene glycols, polypropylene glycols, polybutylene glycols,polythioglycols, poly-arylalkyl ether glycols and copolymer polyetherglycols. Additional representative examples of dihydric phenols andaliphatic diols are described in U.S. Pat. Nos. 3,030,335 and 3,317,466.The polycarbonate may further comprise the residues of one or morebranching agents such as, for example, tetraphenolic compounds,tri-(4-hydroxyphenyl)ethane, pentaerythritol triacrylate and otherscompounds as disclosed in U.S. Pat. Nos. 6,160,082; 6,022,941;5,262,511; 4,474,999; and 4,286,083. Other suitable branching agents arementioned herein below. In a further example, the polycarbonatecomprises at least 95 mole percent, based on the total moles of diolresidues, of the residues of bisphenol A.

The inherent viscosity of the polycarbonate portion of the blendsaccording to the present invention is preferably at least about 0.3dL/g, more preferably at least 0.5 dL/g. The melt flow of thepolycarbonate portion of the blends according to the present inventionis preferably between 1 and 20, and more preferably between 2 and 18, asmeasured according to ASTM Method D1238 at a temperature of 300° C. andusing a weight of 1.2 kg.

Processes for the preparation of polycarbonates are well known in theart. The linear or branched polycarbonates that can be used in theinvention and disclosed herein are not limited to or bound by thepolycarbonate type or its production method. Generally, a dihydricphenol, such as bisphenol A, is reacted with phosgene with the use ofoptional mono-functional compounds as chain terminators andtri-functional or higher functional compounds as branching orcrosslinking agents. Monofunctional, difunctional, and trifunctionalreactive acyl halides also can used in the preparation of polycarbonatesas terminating compounds (mono-functional), comonomers (di-functional),or branching agents (tri-functional or higher).

For example, the polycarbonate portion of the present blend can beprepared in the melt, in solution, or by interfacial polymerizationtechniques well known in the art. Suitable methods include the steps ofreacting a carbonate source with a diol at a temperature of about 0° C.to 315° C. at a pressure of about 0.1 to 760 mm Hg for a time sufficientto form a polycarbonate. Commercially available polycarbonates that canbe used in the present invention, are normally made by reacting anaromatic diol with a carbonate source such as, for example, phosgene,dibutyl carbonate, or diphenyl carbonate, to incorporate 100 molepercent of carbonate units, along with 100 mole percent diol units intothe polycarbonate. Other representative examples of methods of producingpolycarbonates are described in U.S. Pat. Nos. 5,498,688; 5,494,992; and5,489,665.

Blends of the of polyesters and polycarbonates can be made by methodswhich include the steps of blending the polycarbonate and polyesterportions at a temperature of about 25° C. to 350° C. for a timesufficient to form a clear blend composition. Suitable conventionalblending techniques include the melt method and the solution-preparedmethod. Other suitable blending techniques include dry blending and/orextrusion.

The compositions of the present invention, including the immiscible andhomogeneous blends contained therein, may be prepared by any methodknown in the art and are useful as thermoplastic molding compositionsand for formation of films and single and multilayered articles. Inaddition to physically blending the various components of the blend,homogeneous polyesters blends may be prepared by transesterification ofthe polyester components. Similarly, homogeneous blends of polyamidesmay be prepared by transamidation of the polyamide components.

The melt blending method includes blending the polymers at a temperaturesufficient to melt the first component and second component portions,and thereafter cooling the blend to a temperature sufficient to producea clear blend. The term “melt” as used herein includes, but is notlimited to, merely softening the polymers. Examples of melt mixingmethods generally known in the polymers art are described in Mixing andCompounding of Polymers (I. Manas-Zloczower & Z. Tadmor eds., CarlHanser Verlag publisher, N.Y. 1994).

The solution-prepared method includes dissolving the appropriateweight/weight ratio of the first component and second component in asuitable organic solvent such as methylene chloride or a 70/30 mixtureof methylene chloride and hexafluoroisopropanol, mixing the solution,and separating the blend composition from solution by precipitation ofthe blend or by evaporation of the solvent. Solution-prepared blendingmethods are generally known in the polymers art.

The melt blending method is the preferred method for producing the blendcompositions of the present invention. The melt blending method is moreeconomical and safer than the solution method, which requires the use ofvolatile solvents. The melt blending method also is more effective inproviding clear blends. Any of the clear blends of the present inventionthat can be prepared by solution blending also can be prepared by themelt method. Some of the blends of the present invention, however, canbe prepared by the melt method, but not by the solution-prepared method.Any blending process which provides clear blends of the presentinvention is suitable. One of ordinary skill in the art will be able todetermine appropriate blending methods for producing the clear blends ofthe present invention.

These first and second components of the composition may be compoundedin the melt, for example, by using a single screw or twin screwextruder. They may also be prepared by blending in solution. Additionalcomponents such as stabilizers, flame retardants, colorants, lubricants,release agents, impact modifiers, and the like may also be incorporatedinto the formulation. For example, the compositions can be produced viaa melt extrusion compounding of the first component and the secondcomponent with any other composition components such as, for example,metal catalysts, dyes, toners, fillers, and the like. The compositionmay be formed by dry blending solid particles or pellets of each ofthermoplastic polymers and the polyamide components and then meltblending the mixture in a suitable mixing means such as an extruder, aroll mixer, or the like. When a transamidized, homogeneous blend ofpolyamides is used as the second component, it is advantageous toconduct the processing at a temperature that will cause transamidationbetween the polyamides to occur. Typically, these temperatures rangefrom about 270° C. to about 350° C. Other examples of transamidationtemperatures are about 280° C. to about 350° C. and about 290° C. toabout 340° C. Blending is conducted for a period of time that will yielda well dispersed, immiscible blend. Such may easily be determined bythose skilled in the art. If desired, the composition may be cooled andcut into pellets for further processing, it may be extruded into films,sheets, profiles, and other shaped elements, injection or compressionmolded to form various shaped articles, or it may be formed into filmsand optionally uniaxially or biaxially stretched by means well known inthe art.

The amounts of the first and second components in the immiscible blendmay vary widely. For example, the immiscible blend of our novelcomposition may comprise about 5 to about 99 weight percent of the firstcomponent and about 95 to about 1 weight percent of the secondcomponent, based on the total weight of the composition. Othernon-limiting, representative examples of weight percentages of the firstand second components include about 50 to about 99 weight percent of thefirst component and about 50 to about 1 weight percent of the secondcomponent, about 60 to about 99 weight percent of the first componentand about 40 to about 1 weight percent of the second component, andabout 70 to about 99 weight percent of the first component and about 30to about 1 weight percent of the second component.

Our invention also provides a composition comprising an immiscible blendprepared by a process comprising melt blending:

-   (i) a first component comprising at least one thermoplastic polymer    selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof; and-   (ii) a second component comprising a homogeneous, transamidized    blend of at least 2 polyamides;    wherein the second component (ii) and the first component (i) have a    difference in refractive index, RI(second component)−RI(first    component), of about 0.006 to about −0.0006, and the immiscible    blend has a percent transmittance of at least 75%, and a haze of 10%    or less. The composition includes the various embodiments of the    polyesters, polycarbonates, polyarylates, homogeneous blends, and    polyamides as described above and any combination thereof. For    example, the second component of the composition can comprise a    homogeneous, transamidized blend of at least 2 polyamides in which    transamidation may be accomplished by contacting the polyamides at    elevated temperatures, typically from about 270° C. to about 350° C.    Other examples of transamidation temperatures are about 280° C. to    about 350° C. and about 290° C. to about 340° C.

The homogeneous blend of component (ii) can comprise a first polyamide,comprising aromatic residues, and a second polyamide comprisingaliphatic residues, as described previously. For example, typicalpolyamides that can be used as the second polyamide include, but are notlimited to, nylon 4; nylon 6; nylon 9; nylon 11; nylon 12; nylon 6,6;nylon 5,10; nylon 6,12; nylon 6,11; nylon 10,12; and combinationsthereof. In addition to the polyesters described previously, the firstcomponent can comprise a homogeneous blend of a polyester and apolycarbonate comprising the residues of bisphenol A.

Another aspect of the instant invention is a method for the preparationof a transparent polymer blend, comprising:

-   (A) selecting a first component comprising at least one    thermoplastic polymer selected from polyesters, polycarbonates,    polyarylates, and homogeneous blends thereof;-   (B) determining the refractive index of the first component;-   (C) providing a second component comprising    -   (i) a copolyamide having a mole ratio of aliphatic and aromatic        residues, wherein the mole ratio of aliphatic and aromatic        residues is selected to produce a second component refractive        index that satisfies the following formula:

0.006≦RI(second component)−RI(first component)≦−0.0006

-   -   -   or;

    -   (ii) a homogeneous, transamidized blend of a first and second        polyamide, at least one of the polyamides having aromatic        residues, wherein the weight percentage of the first and second        polyamide is selected to produce a second component refractive        index that satisfies the following formula:

0.006≦RI(second component)−RI(first component)≦−0.0006

-   -   -   wherein RI is refractive index; and

-   (D) melt blending the first and second components to produce an    immiscible blend having a percent transmittance of at least 75%, and    a haze of 10% or less.    Our method includes the various embodiments of the polyesters,    polycarbonates, polyarylates, homogeneous blends, copolyamides, and    polyamides as described previously and any combination thereof. Our    method comprises selecting the first component which may be a    polyester, polycarbonate, polyarylate or homogeneous blend thereof.    The refractive index of the first component may be determined using    methods well known to persons skilled in the art. The second    component, which may comprise as single copolyamide or a    transamidized, homogeneous blend of at least two polyamides, is    tailored to closely match the refractive index of the first    component by selecting the appropriate mixture of aromatic and    aliphatic monomers in the case of a copolyamide, or by selecting a    mixture of polyamides containing the desired mixture of aromatic and    aliphatic residues if a homogeneous blend of polyamides is used. The    choice of the proper ratio of monomers or of polyamides can be    determined, for example, by trial and error, or, in another example,    by plotting the refractive index of various polyamides or    copolyamides containing varying amounts of aromatic residues and    aliphatic residues, and selecting the molar ratio of    aromatic:aliphatic residues or the weight percentage ratio of    polyamides that will give the targeted refractive index. The first    and second components may be melt blended. When the second component    comprises a transamidized, homogeneous blend of at least 2    polyamides, it is desirable to carry out the melt blending step at a    temperature effective for the transamidation process. Typical    transamidation temperature ranges are as described previously.

The thermoplastic polymers also may be selected to match the refractiveindex of the second component. Thus, another aspect of the invention isa method for the preparation of a transparent polymer blend, comprising:

-   (A) selecting a second component comprising    -   (i) a copolyamide having a mole ratio of aliphatic and aromatic        residues; or    -   (ii) a homogeneous, transamidized blend of a first and second        polyamide, at least one of the polyamides having aromatic        residues;-   (B) determining the refractive index of the second component;-   (C) providing a first component comprising at least one    thermoplastic polymer selected from polyesters, polycarbonates,    polyarylates, and homogeneous blends thereof wherein the polyester,    polycarbonate, polyarylate, or homogeneous blend thereof is selected    to produce a first component refractive index that satisfies the    following formula:

0.006≦RI(second component)−RI(first component)≦−0.0006

-   -   wherein RI is refractive index; and

-   (D) melt blending the first and second components to produce an    immiscible blend having a percent transmittance of at least 75%, and    a haze of 10% or less. It is further understood that the above    method also includes any combination of the various embodiments of    the polyesters, polycarbonates, polyarylates, homogeneous blends,    copolyamides, polyamides described previously.

In one example, the blending of thermoplastic polymers to obtain asecond component and first component that have a difference inrefractive index of about 0.006 to about −0.0006 may be illustrated withparticular reference to polycarbonate/polyester blends. For example, thecomplete miscibility of a polycarbonate of bisphenol A and PCTG permitsthe tailoring of refractive index (RI) of the polycarbonate/PCTG blend,by adjusting the polycarbonate/PCTG ratio. By adjusting thepolycarbonate ratio. the refractive index of the first component of thepresent invention may be matched to within about 0.006 to about −0.0006of that of the second component comprising the polyamide barrierpolymers. For example, a polymer may be determined to be a suitablemodifying polymer of the homogeneous polyester/polycarbonate blendsdescribed hereinabove if a clear blend is formed by: 1) blending themodifying polymer with a pre-existing blend containing the polycarbonateand polyester portions, or 2) blending the modifying polymer with thepolycarbonate portion prior to the introduction of the polyesterportion, or 3) blending the modifying polymer with the polyester portionprior to the introduction of the polycarbonate portion, or 4) mixing themodifying polymer, polycarbonate portion and polyester portion alltogether prior to blending.

The clear blends of the present invention can still be modified by theincorporation of modifying polymers to produce performance blends, whichmay not necessarily be clear. For example, polyamides such as nylon 6,6from DuPont, poly(ether-imides) such as ULTEM poly(ether-imide) fromGeneral Electric, polyphenylene oxides such aspoly(2,6-dimethylphenylene oxide) or poly(phenylene oxide)/polystyreneblends such as the NORYL resins from General Electric, polyesters,polyphenylene sulfides, polyphenylene sulfide/sulfones,poly(ester-carbonates) such as LEXAN 3250 poly(ester-carbonate) (GeneralElectric), polycarbonates other than LEXAN polycarbonate from GeneralElectric, polyarylates such as ARDEL D100 polyarylate (Amoco),polysulfones, polysulfone ethers, poly(ether-ketones) or aromaticdihydroxy compounds can be used as blend modifiers to modify propertiesor to reduce flammability. Some of the aromatic dihydroxy compounds usedto prepare these polymers are disclosed in U.S. Pat. No. 3,030,335 andU.S. Pat. No. 3,317,466.

The copolyamide or homogeneous blend of polyamides of the composition ofthe invention can function as a barrier polymer and, as such, improvethe barrier properties of the overall composition. The term “barrierpolymer,” as used herein, means a polymer having one or more of thefollowing properties: (1) a water permeability of 2 gm-mils/100 sq in/24hr or less, as measured by ASTM Method No. F1249 at 38° C.; (2) anoxygen permeability of 5 cc(STP)-mils/100 sq in/24 hrs-atm or less, asmeasured by ASTM Method No. D3985 at 23° C., or (3) a carbon dioxidepermeability of 25 cc(STP)-mils/100 sq in/24 hrs atm or less, asmeasured by ASTM Method No. D1434 at 23° C.

The barrier properties may be enhanced by incorporating a metal catalystto produce an oxygen scavenging composition which catalyzes the reactionof oxygen with one or more polyamides in the composition. Our invention,therefore, further provides an oxygen-scavenging composition comprising:

-   (A) an immiscible blend comprising    -   (i) first component comprising at least one thermoplastic        polymer selected from polyester, polycarbonate, polyarylate, and        homogeneous blends thereof;    -   (ii) a second component comprising a transamidized, homogeneous        blend of at least two polyamides;    -   wherein the second component (ii) and the first component (i)        have a difference in refractive index, RI(second        component)−RI(first component), of about 0.006 to about −0.0006,        and the immiscible blend has a percent transmittance of at least        75%, and a haze of 10% or less; and-   (B) at least one metal selected from Groups 3-12, Rows 4-6 of the    Periodic Table of the Elements.

In addition to a homogeneous blend of one or polyamides, theoxygen-scavenging compositions of the invention also may include asingle copolyamide as described hereinabove for the other embodiments ofthe invention. Thus, the invention also provides an oxygen-scavengingcomposition comprising:

-   (A) an immiscible blend comprising    -   (i) first component comprising at least one thermoplastic        polymer selected from polyester, polycarbonate, polyarylate, and        homogeneous blends thereof;    -   (ii) a second component comprising a copolyamide;    -   wherein the second component (ii) and the first component (i)        have a difference in refractive index, RI(second        component)−RI(first component), of about 0.006 to about −0.0006,        and the immiscible blend has a percent transmittance of at least        75%, and a haze of 10% or less; and-   (B) at least one metal selected from Groups 3-12, Rows 4-6 of the    Periodic Table of the Elements.    It should be further understood the oxygen scavenging compositions    include any combination of the various embodiments of the first and    second components, polyesters, polycarbonates, polyarylates,    homogeneous blends, copolyamides, and polyamides described    hereinabove.

The oxygen-scavenging compositions of the invention can include onemetal selected from Groups 3-12, Rows 4-6 of the Periodic Table of theElements as set forth in the 1984 revision of the Periodic Table by theInternation Union of Pure and Applied Chemistry. Typical oxidationcatalysts include transition metal catalysts which can readilyinterconvert between at least two oxidation states. Examples of metalswhich can be used include copper, nickel, cobalt, iron, manganese, andcombinations thereof. Any amount of catalyst which is effective incatalyzing oxygen scavenging may be used but, typically, the metal willbe used in amounts from about 10 ppm to about 1,000 ppm. Other ranges ofmetal concentration include, about 50 ppm to about 750 ppm, about 10 toabout 500 ppm, about 50 ppm to about 500 ppm, and about 50 to about 300ppm based on the total weight of the oxygen-scavenging composition. Themetal typically may be used as the elemental metal itself, as a metalcomplex containing organic ligands, as an oxide, or as a metal salt.Examples of counterions for metal salts include, but are not limited to,chloride, acetate, acetylacetonate, stearate, palmitate,2-ethylhexanoate, neodecanoate, octanoate, or naphthenate, and mixturesthereof. The metal salt may also be an ionomer, in which case apolymeric counterion is employed. Such ionomers are well known in theart.

In one example, the metal catalyst is cobalt or a compound containingcobalt such as, for example, a cobalt salt. The cobalt may be in the +2or +3 oxidation state. Other examples of metal catalysts are rhodium inthe +2 oxidation state and copper in the +2 oxidation state. The metalsmay be added in salt form, conveniently as carboxylate salts such as,for example, cobalt octanoate, cobalt acetate, or cobalt neodecanoate.The reported amounts are based on the weight of the polymer blends andmeasured on the metal, not its compound weight as added to thecomposition. In the case of cobalt as the metal, typical amounts are atleast 50 ppm, or at least 60 ppm, or at least 75 ppm, or at least 100ppm, or at least 125 ppm. The catalyst can be added neat or in a carrier(such as a liquid or wax) to an extruder or other device for making anarticle, or it can be added in a concentrate with a polyamide polymer,in a concentrate with a polyester polymer, or in a concentrate with theimmiscible blend. The carrier may either be reactive or non-reactivewith the first and second component and either volatile or non-volatilecarrier liquids may be employed. The metal catalyst may be added at avariety of points and by way of a variety of blending protocols duringthe preparation of the oxygen scavenging composition. A particularlyuseful approach is to bring the polyamide and transition metal togetherlate in the preparation of the final blend composition, even as late asin the final melt step before forming the article, so that the oxygenscavenging activity of the polyamide is not prematurely initiated. Insome instances, such as when cobalt is provided as a transition metal,it may be preferred to add the cobalt during blending of first andsecond components, instead of, for example, during the preparation ofthe thermoplastic polymers.

In one embodiment, for example, the first component of theoxygen-scavenging composition can comprise a polyester having anycombination of monomer residues as described previously. For example,the polyester can comprise (a) diacid residues comprising at least 80mole percent, based on the total diacid residues, of the residues of atleast one dicarboxylic acid selected from terephthalic acid, isophthalicacid, naphthalenedicarboxylic acid, and 1,4-cyclohexanedicarboxylicacid, and 0 to about 20 mole percent of the residues of at least onemodifying dicarboxylic acid having 2 to 20 carbon atoms; and (b) diolresidues comprising at least 80 mole percent, based on the total molesof diol residues, of the residues of at least one diol selected fromethylene glycol, 1,4-cyclohexanedimethanol; neopentyl glycol, diethyleneglycol, 1,3-propanediol, 1,4-butanediol, and,2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20 molepercent of the residues of at least one modifying diol having from 3 to16 carbons. In another example, the diacid residues can comprise about60 to 100 mole percent of the residues of terephthalic acid and 0 toabout 40 mole percent of the residues of isophthalic acid and the diolresidues can comprise about 100 mole percent of the residues of1,4-cyclohexanedimethanol. In another example, the diacid residues cancomprise about 100 mole percent, based on the total moles of diacidresidues, of the residues of terephthalic acid. Other specific examplesof polyesters that may be used as the first component include polyesterscomprising: (i) about 80 to about 100 mole percent of the residues ofterephthalic acid and about 50 to about 90 mole percent of the residues1,4-cyclohexanedimethanol and about 10 to about 50 mole percentneopentyl glycol; (ii) about 100 mole percent of the residues ofterephthalic acid and about 10 to about 40 mole percent of the residuesof 1,4-cyclohexanedimethanol and 60 to about 90 mole percent of theresidues of ethylene glycol; and (iii) about 100 mole percent of theresidues of terephthalic acid and about 10 to about 99 mole percent ofthe residues of 1,4-cyclohexanedimethanol, 0 to about 90 mole percent ofthe residues of ethylene glycol, and about 1 to about 25 mole percent ofthe residues of diethylene glycol. The polyester may also furthercomprise about 0.1 to 2 mole %, based on the total diacid residues, ofthe residues of at least one branching agent selected from trimelliticacid, trimellitic anhydride, and pyromellitic dianhydride as describedhereinabove.

The first component may also comprise a homogeneous blend of at leastone polyester and at least one polycarbonate. The polycarbonates thatcan be used in these homogeneous blends have been described previously.

The transamidized, homogeneous blend or the copolyamide can comprise anypolyamide as described previously such as for example, various nylons.It is advantageous, however, that the copolyamide or homogeneous blendof polyamides of the oxygen-scavenging composition comprise the residuesof m-xylylenediamine, p-xylylenediamine, or a combination thereof. Forexample, the second component may comprise a homogeneous blend of afirst polyamide comprising the residues of m-xylylenediamine and adipicacid, and a second polyamide comprising nylon 6, nylon 6,6, or blendsthereof. As a further example, this homogeneous blend may be combined inan immiscible blend with a first component comprising a homogeneousblend of the polyester and a polycarbonate comprising the residues ofbisphenol A. It is desirable also for optimum oxygen scavengingproperties that the copolyamide or homogeneous blend of polyamidescontain 20 mmoles/kg or less of free amino groups. The concentration offree amino groups can be determined using techniques well known topersons having ordinary skill in the art such as, for example, bytitration.

In another example, the oxygen scavenging composition comprises acopolyamide of m-xylylenediamine adipate. The use of a modifiedm-xylylenediamine adipate, in which some of the adipic acid residues, orsome of the m-xylylenediamine residues, or some of both, are replacedwith other residues, can give an oxygen-scavenging composition withimproved oxygen-scavenging properties when compared with compositionscontaining only the m-xylylenediamine adipate homopolymer. Otherpolyamide barrier polymers, as described herein, may also be used aspart of the oxygen scavenging composition.

The compositions of the present invention described hereinabove may beused to fabricate shaped articles such as, for example, sheets, films,tubes, preforms, bottles, or profiles. Such articles may be formed byany means well known to persons skilled in the art such as, for example,by extrusion, calendering, thermoforming, blow-molding, extrusionblow-molding, injection molding, compression molding, casting, drafting,tentering, or blowing.

For example, the compositions of the present invention may be fabricatedinto shaped articles such as, for example, films, by any technique knownin the art. Formation of films can be achieved by melt extrusion, asdescribed, for example, in U.S. Pat. No. 4,880,592, or by compressionmolding as described, for example, in U.S. Pat. No. 4,427,614, or by anyother suitable method. For example, films may be produced by the wellknown cast film, blown film and extrusion coating techniques, the latterincluding extrusion onto a substrate. Such a substrate may also includea tie-layer. Films produced by melt casting or blowing can be thermallybonded or sealed to a substrate using an adhesive. The compositions maybe fabricated into monolayer or multilayer films by any technique knownin the art. For example, monolayer, or multi-layer films may be producedby the well known cast film, blown film and extrusion coatingtechniques, the latter including extrusion onto a substrate.Representative substrates include films, sheets, and woven and nonwovenfabrics. Monolayer, or multilayer films produced by melt casting orblowing can be thermally bonded or sealed to a substrate using anadhesive.

For example, the composition may be formed into a film using aconventional blown film apparatus. The film forming apparatus may be onewhich is referred to in the art as a “blown film” apparatus and includesa circular die head for bubble blown film through which the compositionis forced and formed into a film “bubble.” The “bubble” is ultimatelycollapsed and formed into a film.

The compositions also may be used to form shaped articles throughextrusion blow molding and injection stretch-blow molding. An injectionmolding process softens the copolyamide or homogeneous polyamide blendin a heated cylinder, injecting it while molten under high pressure intoa closed mold, cooling the mold to induce solidification, and ejectingthe molded preform from the mold. Molding compositions are well suitedfor the production of preforms and subsequent reheat stretch-blowmolding of these preforms into the final bottle shapes having thedesired properties. The injection molded preform is heated to suitableorientation temperature in the 100° C. to 150° C. range and thenstretch-blow molded. The latter process consists of first stretching thehot preform in the axial direction by mechanical means such as bypushing with a core rod insert followed by blowing high pressure air (upto 500 psi) to stretch in the hoop direction. In this manner, abiaxially oriented blown bottle is made. Typical blow-up ratios rangefrom 5/1 to 15/1.

The excellent transparency and low haze of the compositions of theinvention enable the preparation of transparent, shaped articles withthe incorporation of substantial amounts of scrap polymer or “regrind.”The term “regrind,” as used herein, is understood to have its commonlyaccepted meaning in art, that is, scrap polymer that recovered from anarticle forming process and ground into smaller particles. Often,regrind is sold as scrap for incorporation into shaped articles in whichthe transparency of the article is immaterial to its application. Forcertain shaped articles such as, for example, bottles and films used inpackaging applications, low haze and high transparency are importantfeatures. The manufacture of these articles, in particular, multilayeredarticles, inherently produces large quantities of scrap polymer whichfrequently cannot be returned to the article-forming process because ofthe formation of unacceptable levels of haze. Because of the close matchin the refractive indices of the first and second components, low haze,transparent, shaped articles may be produced from the compositions ofthe invention with the inclusion of regrind.

Another aspect of our invention, therefore, is a process for forming ashaped article, comprising:

-   (A) melt blending    -   (i) a first component comprising at least one thermoplastic        polymer selected from polyesters, polycarbonates, polyarylates,        and homogeneous blends thereof; and    -   (ii) a second component comprising a copolyamide or a        homogeneous, transamidized blend of at least 2 polyamides;    -   wherein the first component (i) and second component (ii) form        an immiscible blend, the second component and the first        component have a difference in refractive index, RI(second        component)−RI(first component), of about 0.006 to about −0.0006,        and the immiscible blend has a percent transmittance of at least        75%, and a haze of 10% or less;-   (B) forming a shaped article;-   (C) recovering a scrap polymer composition comprising the blended    first and second components (i) and (ii);-   (D) grinding the scrap polymer composition to produce a polymer    regrind;-   (E) optionally, drying the scrap polymer composition; and-   (F) combining the polymer regrind with the first and second    components (i) and (ii) of step (A).    Our process, thus, permits the incorporation of scrap polymer    regrind into the shaped article with retention of low haze and high    transparency. It should be further understood the above process    includes the various embodiments of the first and second components,    polyesters, polycarbonates, polyarylates, homogeneous blends,    copolyamides, polyamides, oxygen-scavenging compositions, and any    combination thereof described hereinabove.

For example, as described previously, the immiscible blend formed fromthe first and second components may further comprise at least one metalselected from Groups 3-12, Rows 4-6 of the Periodic Table of theElements. Examples of metals include copper, nickel, cobalt, iron,manganese, and combinations thereof. Typically, the metal is present inamounts of about 10 to about 500 parts per million by weight of themetal, based on the total weight of the shaped article. The preferredmetal is cobalt.

The shaped article of our inventive process may be formed by any methodsknown in the art and described hereinabove. For example, the shapedarticle may be formed by extrusion, calendering, thermoforming,blow-molding, extrusion blow-molding, injection molding, compressionmolding, casting, drafting, tentering, or blowing.

Although the process of the invention may be used to prepare any shapedarticle, representative articles that may be produced are sheets, films,preforms, tubes, and bottles. These article may have a single layer orcontain from 2 to about 7 layers. The regrind may be incorporated intoone or more of these layers which may comprise from about 50 to 100weight percent regrind based on the weight of the one or more layers.Other examples of regrind levels that can be present in the shapedarticle are 5 to about 95 weight percent, about 10 to about 60 weightpercent, about 15 to about 50 weight, and about 20 to about 30 weightpercent.

The shaped article may comprise multiple layers in which one or more ofthe layers comprise the first and second component as an immiscibleblend or in which the first component and the second component arepresent in separate layers. Thus, another aspect of the instantinvention, is a multilayered, shaped article, comprising:

-   (i) a first layer comprising at least one thermoplastic polymer    selected from polyester, polycarbonate, polyarylate, and homogeneous    blends thereof; and-   (ii) a second layer comprising a transamidized homogeneous blend of    at least two polyamides;    -   wherein the second layer (ii) and the first layer (i) have a        difference in refractive index, RI(second layer)−RI(first        layer), of about 0.006 to about −0.0006, and the shaped article        has a percent transmittance of at least 75%, and a haze of 10%        or less.        The shaped article may include the various embodiments of the        first and second components, polyesters, polycarbonates,        polyarylates, homogeneous blends, copolyamides, polyamides,        oxygen-scavenging compositions, shaped articles, and any        combination thereof described hereinabove.

The multilayered shaped article may be produced by extrusion,calendering, thermoforming, blow-molding, extrusion blow-molding,injection molding, compression molding, casting, drafting, tentering, orblowing. Because of the close match between the refractive indices ofthe first and second layers, the multilayered article may furthercomprise a regrind comprising a mixture of the first and second layers,which may be incorporated into first layer, second layer, or acombination of the first and second layer. Typically, the regrind isabout 5 weight percent to about 60 weight percent of the multilayeredarticle, based on the total weight of the article. Other examples ofweight percentages of regrind in the shaped article are about 10 weightpercent to about 40 weight percent and about 20 weight percent to about30 weight percent of the total weight of the article.

The multilayered article can have from 2 to about 7 layers depending onits intended application. For example, as described above, the shapedarticle may be a sheet, film, tube, bottle, or preform. Complex layeredstructures are possible also. For example, the shaped article can have alayered structure represented by ABA, ABABA, ABCBA, or ACBCA in whichlayer A comprises the first layer (i), layer B comprises the secondlayer (ii), and layer C comprises a regrind comprising a mixture ofscrap first and second layers (i) and (ii), polyester or polycarbonateobtained from post consumer recycle, or a combination thereof. Dependingon the composition of the regrind, it can be advantageous that layer Band layer C have a difference in refractive index, RI(layer B)−R(layerC), of about 0.006 to about −0.0006 to maintain the transparency of thearticle and the ability to incorporate regrind.

In another embodiment, layer A can comprise the second layer (ii), layerB comprises the first layer (i) and layer C comprises a mixture of scrapfirst and second layers (i) and (ii), polyester or polycarbonateobtained from post consumer recycle, or a combination thereof.

In addition, the second layer (ii) of our novel multilayered article canfurther comprise at least one metal selected from Groups 3-12, Rows 4-6of the Periodic Table of the Elements. Examples of metals includecopper, nickel, cobalt, iron, manganese, and combinations thereof.Typically, the metal is present in amounts of about 10 to about 500parts per million by weight of the metal, based on the total weight ofthe shaped article. The preferred metal is cobalt.

In yet another embodiment, the multilayered, shaped article of theinvention can further comprise at least one additional layer comprisingabout 50 to about 100 weight percent of regrind, based on the totalweight of the layer. The additional layer containing the regrind canfurther comprise at least one metal selected from Groups 3-12, Rows 4-6of the Periodic Table of the Elements. Examples of metals includecopper, nickel, cobalt, iron, manganese, and combinations thereof.Typically, the metal is present in amounts of about 10 to about 500parts per million by weight of said metal, based on the total weight ofsaid shaped article. The preferred metal is cobalt.

As noted above, the multilayered, shaped article may comprise thevarious embodiments of the shaped articles, thermoplastic polymers,polyamides, immiscible blends, homogeneous blends, and oxygen scavengingcompositions as described earlier. For example, the at least onethermoplastic polymer may comprise a linear or branched polyestercomprising at least 80 mole percent, based on the total diacid residues,of the residues of at least one dicarboxylic acid selected fromterephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, and1,4-cyclohexanedicarboxylic acid, and 0 to about 20 mole percent of theresidues of at least one modifying dicarboxylic acid having 2 to 20carbon atoms; and (b) diol residues comprising at least 80 mole percent,based on the total moles of diol residues, of the residues of at leastone diol selected from ethylene glycol, 1,4-cyclohexanedimethanol;neopentyl glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol,and, 2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20mole percent of the residues of at least one modifying diol having from3 to 16 carbons; and the one or more barrier polymers comprise ahomogeneous blend of a first polyamide comprising the residues ofm-xylylenediamine and adipic acid, and a second polyamide comprisingnylon 6, nylon 6,6, or blends thereof. For example, the thermoplasticpolymer may comprise a branched polyester. In a further example, thethermoplastic polymer further comprise a homogeneous blend of thepolyester and a polycarbonate comprising the residues of bisphenol A.

The multilayered, shaped articles of the present invention may beprepared by any method known to persons of ordinary skill in the art.For example, the shaped articles can be formed by any conventionaltechnique for forming films, including lamination, extrusion lamination,coinjection, stretch-blow molding and coextrusion blowmolding, and maybe illustrated with particular reference to a typical method for makingmultilayer film by coextrusion. For example, the first and secondcomponents, as well as any optional layers, are fed into infeed hoppersof the extruders of like number, each extruder handling the material forone or more of the layers. Typically, for compositions of the presentinvention, the first and second components each will be heated to atemperature of about Tg+100° C. to about Tg+300° C. before and duringextrusion, wherein Tg is the glass transition temperature of the firstor second component as measured by differential scanning calorimetry.The melted streams from the individual extruders are fed into a singlemanifold co-extrusion die. While in the die, the layers are juxtaposedand combined, then emerge from the die as a single multiple layer filmof polymeric material. After exiting the die, the film is cast onto afirst controlled temperature casting roll, passes around the first roll,and then onto a second controlled temperature roll, which is normallycooler than the first roll. The controlled temperature rolls largelycontrol the rate of cooling of the film after it exits the die. Inanother method, the film forming apparatus may be one which is referredto in the art as a blown film apparatus and includes a multi-manifoldcircular die head for bubble blown film through which the filmcomposition is forced and formed into a film bubble which may ultimatelybe collapsed and formed into a film. Processes of coextrusion to formfilm and sheet laminates are generally known. Alternatively theindividual layers may first be formed into sheets and then laminatedtogether under heat and pressure with or without intermediate adhesivelayers.

The transparency and low haze of the compositions of the invention alsoenable the preparation of multilayered, transparent, shaped articleswith the incorporation of substantial amounts of scrap polymer or“regrind.” Our invention, therefore, also provides a process for forminga multilayered, shaped article, comprising:

-   (i) heating a first component comprising at least one thermoplastic    polymer selected from polyesters, polycarbonates, polyarylates, and    homogeneous blends thereof to a temperature of about Tg+100° C. to    about Tg+300° C. of the first component;-   (ii) heating a second component comprising a copolyamide or a    transamidized, homogeneous blend of at least two polyamides to a    temperature of about Tg+100° C. to about Tg+300° C. of the second    component;-   (iii) forming a shaped article having the first and second    components in separate layers;-   (iv) recovering scrap first and second components;-   (v) grinding the scrap first and second components to produce a    regrind;-   (vi) optionally, drying the regrind; and-   (vii) combining the regrind with the first component, second    component, or a combination thereof, of steps (i) and (ii);    wherein the second component of step (ii) and the first component of    step (i) of have a difference in refractive index, RI(second    component)−RI(first component), of about 0.006 to about −0.0006, and    the shaped article has a percent transmittance of at least 75%, and    a haze of 10% or less. The process may include the various    embodiments of the first and second components, polyesters,    polycarbonates, polyarylates, homogeneous blends, copolyamides,    polyamides, oxygen-scavenging compositions, shaped articles,    article-forming processes, and any combination thereof described    hereinabove.

Our process enables the incorporation of substantial amounts of regrindinto shaped article while maintaining low haze and high transparency.The regrind will typically comprise a mixture of the first and secondcomponents of steps (i) and (ii) that are produced as scrap during thearticle-forming process, but any polymer material can be used as long asits refractive index differs from the that second component by about0.006 to about −0.0006. The regrind material of the process can becombined with the first component of step (i), the second component ofstep (ii) or a combination of the first and second components. Theregrind can be from about 5 weight percent to about 60 weight percent ofthe shaped article, based on the total weight of the shaped article.Other representative examples of regrind content for the shaped articleof the process of the invention are about 10 weight percent to about 40weight percent of the shaped article and about 20 weight percent toabout 30 weight percent of the shaped article.

The multilayered article of our process can have from 2 to about 7layers depending on its intended application. For example, as describedabove, the multilayered, shaped article may be a sheet, film, tube,bottle, or preform. Complex layered structures are possible also. Forexample, the shaped article can have a layered structure represented byABA, ABABA, ABCBA, or ACBCA in which layer A comprises the firstcomponent of step (i), layer B comprises the second component of step(ii), and layer C comprises a regrind comprising a mixture of scrapfirst and second components from steps (i) and (ii), polyester orpolycarbonate obtained from post consumer recycle, or a combinationthereof. Depending on the composition of the regrind, it can beadvantageous that layer B and layer C have a difference in refractiveindex, RI(layer B)−R(layer C), of about 0.006 to about −0.0006 tomaintain the transparency of the article and the ability to incorporateregrind.

In another embodiment, layer A can comprise the second component of step(ii), layer B comprises the first component of step (i) and layer Ccomprises a mixture of scrap first and second components of steps (i)and (ii), polyester or polycarbonate obtained from post consumerrecycle, or a combination thereof.

In addition, the second component of step (ii) of our novel multilayeredarticle can further comprise at least one metal selected from Groups3-12, Rows 4-6 of the Periodic Table of the Elements. Examples of metalswhich can be used include copper, nickel, cobalt, iron, manganese, andcombinations thereof. Typically, the metal is present in amounts ofabout 10 to about 500 parts per million by weight of the metal, based onthe total weight of the shaped article. The preferred metal is cobalt.

In yet another embodiment, step (iii) of the process of the inventioncan further comprise forming at least one additional layer comprisingabout 50 to about 100 weight percent of regrind, based on the totalweight of the layer. The additional layer containing the regrind canfurther comprise at least one metal selected from Groups 3-12, Rows 4-6of the Periodic Table of the Elements. Examples of metals includecopper, nickel, cobalt, iron, manganese, and combinations thereof.Typically, the metal is present in amounts of about 10 to about 500parts per million by weight of said metal, based on the total weight ofsaid shaped article. The preferred metal is cobalt.

As noted above, the multilayered, shaped article may comprise thevarious embodiments of the shaped articles, thermoplastic polymers,polyamides, immiscible blends, homogeneous blends, and oxygen scavengingcompositions as described earlier. For example, the at least onethermoplastic polymer may comprise a polyester comprising at least 80mole percent, based on the total diacid residues, of the residues of atleast one dicarboxylic acid selected from terephthalic acid, isophthalicacid, naphthalenedicarboxylic acid, and 1,4-cyclohexanedicarboxylicacid, and 0 to about 20 mole percent of the residues of at least onemodifying dicarboxylic acid having 2 to 20 carbon atoms; and (b) diolresidues comprising at least 80 mole percent, based on the total molesof diol residues, of the residues of at least one diol selected fromethylene glycol, 1,4-cyclohexanedimethanol; neopentyl glycol, diethyleneglycol, 1,3-propanediol, 1,4-butanediol, and,2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20 molepercent of the residues of at least one modifying diol having from 3 to16 carbons; and the one or more barrier polymers comprise a homogeneousblend of a first polyamide comprising the residues of m-xylylenediamineand adipic acid, and a second polyamide comprising nylon 6, nylon 6,6,or blends thereof. For example, the thermoplastic polymer may comprise abranched polyester. In a further example, the thermoplastic polymerfurther comprise a homogeneous blend of the polyester and apolycarbonate comprising the residues of bisphenol A.

Another embodiment of our invention further is a process for forming amultilayered shaped article, comprising:

-   (A) heating a first component comprising (i) at least one polyester    comprising: (a) diacid residues comprising at least about 95 mole    percent, based on the total diacid residues, of the residues of    terephthalic acid; and (b) diol residues comprising at least 95 mole    percent, based on the total moles of diol residues, of the residues    of at least one diol selected from ethylene glycol and    1,4-cyclohexanedimethanol; (ii) at least one polycarbonate    comprising the residues of bisphenol A; or (iii) a homogeneous blend    thereof to a temperature of about Tg+100° C. to about Tg+300° C. of    the first component;-   (B) heating a second component comprising a transamidized,    homogeneous blend of a polyamide comprising diamine and diacid    residues, the polyamide comprising about 100 mole percent, based on    the total diamine residues, of the residues of m-xylylenediame and    about 100 mole percent, based on the total diacid residues, of the    residues of adipic acid, and at least one polyamide selected from    nylon 6 and nylon 6,6 to a temperature of about Tg+100° C. to about    Tg+300° C. of the second component-   (C) forming a shaped article having the first and second polymer    compositions in separate layers;-   (D) recovering scrap first and second components;-   (E) grinding the scrap first and second components to produce a    regrind;-   (F) optionally, drying the regrind; and-   (G) combining the regrind with the first component, second    component, or a combination thereof, of steps (A) and (B);    wherein the second component of step (B) and the first component of    step (B) have a difference in refractive index, RI(second    component)−RI(first component), of about 0.006 to about −0.0006, and    the shaped article has a percent transmittance of at least 75%, and    a haze of 10% or less. The process may include the various    embodiments of the first and second components, polyesters,    polycarbonates, polyarylates, homogeneous blends, copolyamides,    polyamides, oxygen-scavenging compositions, shaped articles,    article-forming processes, and any combination thereof described    hereinabove.

As described previously, the regrind may comprise a mixture of the firstand second components (i) and (ii) and can be combined with the firstcomponent (i), second component (ii), or a combination thereof. Theregrind can be from about 5 weight percent to about 60 weight percent ofthe shaped article, based on the total weight of the shaped article.Other representative examples of regrind content for the shaped articleof the process of the invention are about 10 weight percent to about 40weight percent of the shaped article and about 20 weight percent toabout 30 weight percent of the shaped article.

The polyester of the process can comprises diacid residues comprising atleast about 95 mole percent of the residues of terephthalic acid and canhave a range of diol compositions. For example, the polyester cancomprise diol residues comprising about 1 to about 5 mole percent of theresidues of 1,4-cyclohexanedimethanol and about 99 to about 95 molepercent of the residues of ethylene glycol. Other examples of diolcompositions for the polyester of our process include, but are notlimited to: (i) diol residues comprising about 29 to about 33 molepercent of the residues of 1,4-cyclohexanedimethanol and about 71 toabout 67 mole percent of the residues of ethylene glycol; (b) diolresidues comprising about 45 to about 55 mole percent of the residues of1,4-cyclohexanedimethanol and about 55 to about 45 mole percent of theresidues of ethylene glycol; (iii) residues comprising about 60 to about65 mole percent of the residues of 1,4-cyclohexanedimethanol and about40 to about 35 mole percent of the residues of ethylene glycol; (iv)diol residues comprising about 79 to about 83 mole percent of theresidues of 1,4-cyclohexanedimethanol and about 21 to about 17 molepercent of the residues of ethylene glycol; and (v) diol residuescomprising about 100 mole percent of the residues of1,4-cyclohexanedimethanol. The polyester may further comprise about 0.1to 2 mole %, based on the total diacid residues, of the residues of atleast one branching agent selected from trimellitic acid, trimelliticanhydride, and pyromellitic dianhydride.

In a further example, the thermoplastic polymer may further comprise ahomogeneous blend of the polyester and a polycarbonate comprising theresidues of bisphenol A. Each of the polyester and polycarbonate may belinear or branched.

In addition, the second component of step (ii) of our novel process canfurther comprise at least one metal selected from Groups 3-12, Rows 4-6of the Periodic Table of the Elements. Examples of metals which can beused include copper, nickel, cobalt, iron, manganese, and combinationsthereof. Typically, the metal is present in amounts of about 10 to about500 parts per million by weight of the metal, based on the total weightof the shaped article. The preferred metal is cobalt.

In yet another embodiment, step (C) of the process of the invention canfurther comprise forming at least one additional layer comprising about50 to about 100 weight percent regrind, based on the total weight of thelayer. The additional layer containing the regrind can further compriseat least one metal selected from Groups 3-12, Rows 4-6 of the PeriodicTable of the Elements. Examples of metals include copper, nickel,cobalt, iron, manganese, and combinations thereof. Typically, the metalis present in amounts of about 10 to about 500 parts per million byweight of said metal, based on the total weight of said shaped article.The preferred metal is cobalt.

The shaped articles of the invention may be further oriented bystretching which may improve the barrier properties of the article. Asdescribed earlier, it may be desirable to incorporate other conventionaladditives or modifying polymers with the polymeric compositions of thepresent invention. For example, there may be added antioxidants, heatand light stabilizers, dyes, antistatic agents, lubricants,preservatives, processing aids, slip agents, antiblocking agents,pigments, flame retardants, blowing agents, and the like. More than oneadditive may be used. The additive may be present in any desired amount,but typically are not present at more than about 20 weight percent,preferably not more than 10 weight percent, of the total weight of theshaped article.

The polymer compositions, oxygen-scavenging compositions, and shapedarticles prepared therefrom also may comprise up to about 30 weightpercent, preferably less than about 20 weight percent, of certainplatelet particles derived from at least one layered silicate materialto improve their barrier properties. The platelet particles can bemodified with at least one ammonium compound. The amount of plateletparticles may be determined by measuring the residual ash of thepolymer-platelet particle compositions when treated in accordance withASTM D5630-94. The gas barrier improvement typically increases withincreasing concentration of platelet particles in the composite. Whileamounts of platelet particles as low as about 0.01 percent provideimproved barrier (especially when well dispersed and ordered),compositions having at least about 0.5 weight percent of the plateletparticles are preferred because they display desirable improvements ingas permeability.

Generally layered silicate materials are a dense agglomeration ofplatelet particles which are closely stacked together like cards. Theplatelet particles of the present invention have a thickness of lessthan about 2 nm and a diameter in the range of about 10 to about 5000nm. For the purposes of this invention, measurements refer only to theplatelet particle and not to the ammonium compounds or any additionaldispersing aids and treatment compounds which might be used. Suitableplatelet particles are derived from layered silicate materials that aretypically free flowing powders having a cation exchange capacity betweenabout 0.3 and about 3 meq/g and preferably between about 0.8 and about1.5 meq/g. Examples of suitable layered silicate materials includemica-type layered phyllosilicates, including clays, smectite clays,sodium montmorillonite, sodium hectorite, bentonites, nontronite,Beidelite®, volonsloite, saponite, sauconite, magadite, kenyaite,synthetic sodium hectorites, and the like. Clays of this nature areavailable from various companies including Southern Clay Products andNanocor, Inc. The most preferred platelet particles are derived forsodium bentonite or sodium montmorillonite. Such clays are readilyavailable in the U.S., known as Wyoming type montmorillonite, and otherparts of the world, including the Kunipia clays available from KunimineIndustries, Inc.

The layered silicate materials are typically treated to improvedispersion into the polymer composition. Many useful clay treatments areknown in the art, and these treatments may also be used before, after,or during incorporation of the layered silicate materials into thecomposites of this invention without deviating from the scope of thisinvention. Examples of useful treatments include, but are not limited totreatments with silane compounds, expanding agents, polymers andoligomers, dispersing aids, organic cation salts, and theircombinations.

Examples of useful treatment with silane compounds include thosetreatments disclosed in International Publication No. WO 93/11190.Examples of useful silane compounds includes(3-glycidoxypropyl)trimethoxysilane, 2-methoxy(polyethyleneoxy)propylheptamethyl trisiloxane, octadecyl dimethyl (3-trimethoxysilylpropyl)ammonium chloride and the like.

Examples of useful treatment with expanding agents include oligomericpolymers well known in the art. Representative polymers and oligomersfor treating clays include those disclosed in U.S. Pat. Nos. 5,552,469and 5,578,672. Many dispersing aids are known, covering a wide range ofmaterials including water, alcohols, ketones, aldehydes, chlorinatedsolvents, hydrocarbon solvents, aromatic solvents, and the like orcombinations thereof.

EXAMPLES

General: The invention is further illustrated by the following examples.The glass transition temperatures (Tg's) of the polyesters, polyamides,and blends were determined by ASTM Method D3418 using a TA Instruments2920 differential scanning calorimeter (DSC) at a scan rate of 20°C./min. Heat Deflection Temperature was determined by ASTM Method D648,and Notched Izod Impact Strength was performed according to ASTM MethodD256. Flexural properties were determined according to ASTM Method D790.The tensile properties of the blends were determined according to ASTMMethod D638 at 23° C. The inherent viscosity of the polyesters wasdetermined in 60/40 (wt/wt) phenol/tetrachloroethane at a concentrationof 0.5 g/100 mL at 25° C. The diol content of the polyester portion ofthese blends was determined by proton nuclear magnetic resonancespectroscopy ('H NMR). The miscibility of the blends was determined bydifferential scanning calorimetry of pressed films and molded objects.

Haze values were determined by ASTM Method D1003 (% Haze=100*DiffuseTransmission/Total Transmission) using a HunterLab UltraScan Sphere 8000Colorimeter manufactured by Hunter Associates Laboratory, Inc., Reston,Va., using Hunter's Universal Software (version 3.8). Calibration andoperation of the instrument was carried out according to the HunterLabUser Manual. Diffuse transmission was obtained by placing a light trapon the other side of the integrating sphere from the sample port, thuseliminating the straight-thru light path. Only light scattered bygreater than 2.5 degrees was measured. Total transmission includesmeasurement of light passing straight-through the sample and alsooff-axis light scattered to the sensor by the sample. The sample wasplaced at the exit port of the sphere so that off-axis light from thefull sphere interior is available for scattering. Clarity was determinedvisually and with haze measurements. For blends and the variouscompositions of the invention, haze and % transmittance were determinedby forming the composition into a sheet, film, or plaque having athickness of ⅛ inch or less and measuring the haze according to theabove procedure. For shaped articles, including multilayer shapedarticles, the haze and % transmittance were determined by cutting out asmall (i.e., 1×1 cm) section of the article, having a thickness of ⅛inch or less, and measuring the haze according the procedure describedabove.

Refractive index was measured at 633 nm with a Metricon Prism Coupler™model 2010 refractometer (available from Metricon Inc.) and is reportedas the average of the refractive indices measured in 3 orthogonaldirections (extrusion or stretch, transverse, and thickness directions).Oriented films were produced on a TM Long film stretcher (named for theproducer) which uniaxially or biaxially stretches samples of pressed,blown, or extruded film. The operation of the film stretcher was basedupon the movement of two drawbars at right angles to each other uponhydraulically driven rods. There was a fixed draw bar opposed to eachmoving draw bar. These pairs of opposed moving and fixed draw bars, towhich the four edges of the film specimen are attached, form the twoaxes at right angles to each other along which the specimen is stretchedin any stretch ratio up to four or seven times original size, dependingon the machine being used. Samples were placed in grips on the machineand heated prior to stretching if desired. The outputs from the deviceare stress versus elongation data (if desired) at the temperature of theexperiment and the stretched film.

Oxygen permeabilities of films were determined using Ox-Tran OxygenPermeation instruments manufactured by MOCON, Inc. Minneapolis, Minn.Oxygen permeabilities were calculated from the known area of the filmsin test, thickness of the film, partial pressure differential of oxygenacross the film, and the measured steady state transmission rate. In thecase of samples which exhibit active oxygen scavenging, the measuredflux is not truly at steady state, since the transmission rate canslowly change as the efficiency of the oxygen scavenging reactionchanges with time. However, in these instances, the oxygen transmissioncan often be considered to be at pseudo-steady state during the durationof permeation measurement. In the active oxygen scavenger samplesincluded in the examples which follow, little to no change in scavengerefficiency was evident during the course of the measurements andpermeabilities were calculated from the measured pseudo-steady statetransmission rates.

Comparative Examples 1-12

The copolyesters listed in Table 1 were prepared from terephthalic acid,ethylene glycol, and 1,4-cyclohexanedimethanol (CHDM). The amount ofCHDM in the polyesters is shown in Table 1. Example F contains 100% CHDM(0% ethylene glycol) but 26 mole % of the acid portion is isophthalicacid instead of terephthalic acid

TABLE 1 CHDM (mole %) in Refractive Index Polyester polyester Tg ofpolyester A 1.5 81 1.5708 B 31 83 1.5644 C 50 84 1.5593 D 62 86 1.5573 E81 91 1.5547 F 100 88 1.5519

The copolyesters and MXD6 6121 polyamide (containing 100 mole %m-xylylene and 100 mole % adipic acid, available from MitsubishiCorporation) were dried overnight at 70° C. Each of these copolyesterswere bag blended with a MXD6 at 1, 3, and 5 wt % and fed to a Sterling1.5 inch single screw extruder at 90 rpm under the following temperaturesettings (degrees C.) to form a blend:

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 240 250 260 260 260

The blends were dried overnight at 70° C. and then injection molded into⅛ inch thick 4″ square plaques at 270° C. on a Toyo 90 injection moldingmachine. The refractive index of the MXD6 was measured to be 1.5824. Theresulting haze values and the result of the subtraction of therefractive index of the polyester from the refractive index of the nylonare shown in Table 2:

TABLE 2 Poly- Poly- Total Exam- ester ester MXD6 % TransmissionRI(nylon) − ple Type (wt %) (wt %) Haze (%) RI(polyester) C-1 A 99 1 5.282.8 0.0116 C-2 A 97 3 14.3 81.6 0.0116 C-3 A 95 5 29.8 82.0 0.0116 C-4B 99 1 5.1 79.5 0.0180 C-5 B 97 3 22.4 70.7 0.0180 C-6 B 95 5 42.9 62.40.0180 C-7 C 99 1 8.5 80.7 0.0231 C-8 C 97 3 31.0 70.4 0.0231 C-9 C 95 550.7 62.6 0.0231 C-10 D 99 1 11.5 77.6 0.0251 C-11 D 97 3 59.0 63.30.0231 C-12 D 95 5 81.6 53.5 0.0231

Examples 13-24, 27-29, 37-32, 34-36, 38 and Comparative Examples 25-26,30, 33, 36-37, and 39

Nylon 6 (available as Zytel® 7335F from DuPont) and MXD6 (grade 6121)were dried at 120° C. for 48 hours and bag blended in various ratios.Polyamide bag blends were then fed to a Sterling 1.5 inch single screwextruder at 90 rpm under the following conditions (° C.) to form ahomogeneous, transamidized blends as indicated by the presence of asingle, composition dependent Tg value for each blend. The Tg values areshown in Table 3.

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 250 270 300 300 300

Portions of the transamidized nylon blends or MXD6 were dried overnightat 120° C. and then either injection molded into ⅛ inch thick samples at240° C. on a Toyo 90 injection molding machine or extruded into 15 milthick film at 240° C. The films were prepared by the following extrusionprocess: The extruder used was a conventional 2.54 cm diameter Killianextruder, 24:1 L:D (length:diameter) ratio, fitted with a feed screwwith 3:1 compression ratio and twisted maddock mixing section. Theconventional feedblock was used to convey the melt to a conventional15.24 cm coathanger die. A 2-roll cast film downstack configuration wasused for quenching the melt. These films were then stretched on theTM-Long 4× in each direction at 95° C. The properties of these filmsbefore stretching are shown in Table 3 and after stretching are shown inTable 3A. It should be noted that oxygen permeabilities in Tables 3Awere measured at 30° C. and 50% relative humidity with 100% O₂ as thetest gas.

TABLE 3 Film Properties Before Stretching Oxygen Nylon PermeabilityThick- Refrac- Exam- MXD6 6 Tg (cc*mil/ ness tive ple (wt %) (wt %) (°C.) 100 in²*day*atm) (mil) Index 13 100 0 88 0.533 15.003 1.5824 14 95 587 0.440 15.000 1.5772 15 90 10 83 0.100 14.465 1.5739 16 87 13 83 0.06314.498 1.5724 17 85 15 81 0.413 14.065 1.5717 18 75 25 77 1.266 15.2601.5655 19 73 27 76 1.060 14.065 1.5641 20 70 30 75 1.317 14.535 1.561721 65 35 72 1.334 14.755 1.5599 22 62 38 72 0.740 16.385 1.5575 23 60 4070 0.709 14.630 1.5536 24 0 100 44 1.5318

TABLE 3A Film Properties After Stretching Oxygen Permeability MXD6 Nylon6 (cc * mil/ Thickness Example (wt %) (wt %) (100 in² * day * atm) (mil)13 100 0 0.230 0.900 14 95 5 0.238 0.930 15 90 10 0.263 0.850 16 87 130.340 0.860 17 85 15 0.325 0.820 18 75 25 0.499 0.900 19 73 27 1.4020.885 20 70 30 0.622 0.880 21 65 35 0.215 0.970 22 62 38 0.847 1.095 2360 40 0.982 0.995 24 0 100

To generate examples and comparative examples shown in Table 4, portionsof the transamidized blends or MXD6 were dried overnight between 70 and120° C. and then compounded with the polyesters of Table 1. Thepolyesters were dried overnight between 70 and 120° C. Each of thesepolyesters of Table 1 were bag blended with 10 wt % of selectedtransamidized blends of Table 3 or MXD6 and fed to a Sterling 1.5 inchsingle screw extruder at 90 rpm under the following temperature settings(° C.) to form an immiscible blend:

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 240 260 280 280 280The blends were dried overnight at 70° C. and then injection molded into⅛ inch thick 4″ square plaques at 270° C. on a Toyo 90 injection moldingmachine. The resulting haze values and the result of the subtraction ofthe refractive index of the polyester from the refractive index of thenylon are shown in Table 4.

To generate example 38 and comparative example C-39, the transamidizedblend from example 20 of Table 3 was dried overnight at 70° C. and thenbag blended with either polyester A or C of Table 1. The polyesters werealso dried overnight between 70 and 120° C. The bag blends were theninjection molded into ⅛ inch thick 4″ square plaques at 270° C. on aToyo 90 injection molding machine. The resulting haze values and theresults of the subtraction of the refractive index of the polyester fromthe refractive index of MXD6 or the nylon blends are shown in Table 4.

TABLE 4 Polyester blends with homogeneous MXD6/Nylon 6 blends CHDM BlendBlend Polyester Blend Example (mole %) MXD6 Nylon 6 Haze Total RI(nylon)− Example Type of Table 3 in polyester (wt %) (wt %) % % Trans.RI(polyester) C-25 A 13 1.5 100 0 28.1 71.1 0.0116 C-26 A 14 1.5 95 513.5 76.0 0.0064 27 A 15 1.5 90 10 6.3 77.8 0.0031 28 A 16 1.5 87 13 6.978.1 0.0016 29 A 17 1.5 85 15 7.7 77.9 0.0009 C-30 B 17 31 85 15 21.381.8 0.0073 31 B 18 31 75 25 5.0 86.5 0.0011 32 B 19 31 73 27 8.5 85.4−0.0003 C-33 B 20 31 70 30 16.2 84.1 −0.0027 34 C 20 50 70 30 4.1 86.80.0024 36 C 21 50 65 35 8.3 84.5 0.0006 C-36 C 22 50 62 38 13.6 82.8−0.0018 C-37 C 23 50 60 40 19.3 80.2 −0.0057 38 C 20 50 70 30 3.7 86.30.0024 C-39 A 20 3.5 70 30 33.0 69.9 −0.0091

Example 40

In this prophetic example, a synthetic route to a polyamide with theappropriate refractive index is employed instead of blending twopolyamides as in the above Examples 13-24. Any method known in the artcan be used to produce these directly synthetic polyamides. Thepolyamides are generally prepared by melt phase polymerization from adiacid-diamine complex which may be prepared either in situ or in aseparate step. In either method, the diacid and diamine are used asstarting materials. Alternatively, an ester form of the diacid may beused, preferably the dimethyl ester. If the ester is used, the reactionmust be carried out at a relatively low temperature, generally 80 to120° C., until the ester is converted to an amide. The mixture is thenheated to the polymerization temperature. For this prophetic example,the polyamide synthesized is poly(m-xylylene pimelamide) which issynthesized from the diamine m-xylylenediamine and the diacid pimelicacid. This polyamide is then blended with 90 wt % of the copolyester Ain Table 1, in accordance with methods disclosed in Examples 25-39. Thedifference in refractive index between these the copolyester A andpoly(m-xylylene pimelamide) is predicted to be 0.0034 and is predictedto be transparent. The resulting blend is predicted to have a haze valueof less 10% and a transmittance of greater than 75%.

Examples 42-43 and 47-49 and Comparative Examples 41, 44-46, and 50-53Monolayer Films of Blends and Oxygen-Scavenging Compositions

Several MXD6/N6 transamidized blends were prepared in the mannerdiscussed above for examples 13-24 and are given in Table 5. Therefractive index values listed in Table 5 were measured on 15 mil filmsof these transamidized blends in the manner discussed above for examples13-24. Three wt % or 5 wt % of either these transamidized MXD6/N6preblends or MXD6 were bag blended with several of the copolyesters fromTable 1 as per Table 6. These pellet blends were then dried overnight at60° C.-70° C. and then fed to a Killian 1.0 inch single screw extruderat 95 rpm at the temperatures indicated in table 7 to form nominally 30mil thick films from the immiscible blend. All films containing pureMXD6 had haze values greater than 10%. The films where the refractiveindex of nylon blend was matched to the refractive index ofcorresponding polyester within a range of 0.006 to −0.0006 were clear(haze 10%).

TABLE 5 Homogeneous MXD6 - Nylon 6 Blends Refractive Tg NylonComposition Index (° C.) W - Transamidized MXD6/23 wt % 1.5650 78 Nylon6 preblend X - Transamidized MXD6/30 wt % 1.5617 75 Nylon 6 preblend Y -Transamidized MXD6/41 wt % 1.5528 70 Nylon 6 preblend Z - TransamidizedMXD6/50 wt % 1.5472 66 Nylon 6 preblend MXD6 MXD6 1.5824 88

To produce oxygen-scavenging compositions, a concentrate containingcobalt neodecanoate was added to two of the films. This concentrate wasprepared as follows. Separate feeds of polyester type C and cobaltneodecanoate, in the form of a pastille and supplied as Cobalt Ten-Cem™22.5% (available from OMG Corp.) were fed into a 57 mm twin-screwextruder and melt blended at barrel set points of approximately 235° C.Molten polymer exited the extruder in the form of approximate 0.08″diameter strands which were water quenched and cut into approximate0.125″ length pellets. The ratio (by weight) of polyester to polyamideto concentrate was 93:5 to 5 to 1.5 and the concentration of cobaltmetal in the concentrate was such that this ratio resulted in about 140to 150 ppm cobalt in the final blended film. The samples which containedcobalt exhibited excellent oxygen scavenging capacity. These samples,which were mounted on the Ox-Tran permeation instrument 1 week afterextrusion, had average apparent permeabilities under these conditions ofless than 0.15 cc(STP)*mil/100 in²/day/atm for over 6 months.

TABLE 6 30 mil Monolayer Film Results Melt Total Trans. RI(nylon) −Oxygen Example Polyester Nylon Temp % Haze (%) RI(polyester)Permeability* C-41 B 3% MXD6 250° C. 22.72 88.1 0.0180 42 B 3% W 250° C.1.13 90.5 0.0006 43 C 250° C. 0.47 90.8 n/a 25.06 C-44 C 3% MXD6 250° C.35.90 87.8 0.0231 C-45 C 5% MXD6 280° C. 53.57 87.7 0.0231 13.62 C-46 C5% MXD6 + Co 280° C. 34.12 86.2 0.0231 0.20 47 C 3% X 250° C. 1.00 90.70.0024 48 C 5% X 280° C. 0.98 90.6 0.0024 20.70 49 C 5% X + Co 280° C.1.10 90.4 0.0024 0.09 C-50 E 3% MXD6 290° C. 27.12 85.6 0.0277 C-51 E 3%Y 290° C. 2.99 90.8 −0.0019 C-52 F 3% MXD6 250° C. 64.06 87.9 0.0305C-53 F 3% Z 250° C. 2.28 92.3 −0.0047 *apparent permeabilities (averageof 2 films per composition and 3 permeability measures per film) fifteendays after mounting on the instrument measured at 23° C. and about 60 to80% relative humidity using air as the upstream test gas.

Example 56 and Comparative Examples 54-55 Regrind of Multilayer Films

Multilayer films were prepared by co-extruding two 15 mil layers ofpolyester C around a 4 mil thick layer of either MXD6 or transamidizedMXD6/30 wt % N6 blend “X.” This is referred to as an “ABA” structurewhere the “A” layers are the outer layers and the “B” layer is theinterior layer. A Killian 1″ extruder was used to extrude the outerlayers from polyester C at a temperature of 265° C. A 0.75″ Killianextruder was used to extrude the inner layers at a temperature of 285°C. for the MXD6 and 275° C. for the transamidized MXD6/30 wt % Nylon 6blend “X.” In order to simulate the reuse of these multilayer films asregrind in a monolayer structure, these multilayer films were thenground up and dry blended with additional polyester C pellets at a 50/50ratio. This dry blend was then dried at 70 C and extruded on a Killian1″ extruder at a temperature of 240° C. into 20 mil films. Haze valuesare shown in table 7. The coextruded films all have haze values lessthan 2%. However, when these films are reground and blended with neatpolyester “C,” the film containing the C/MXD6 regrind blend the valuesincrease above 10%. The film containing the “C/X” regrind remains clear.

TABLE 7 20 mil Monolayer films produced 30 mil ABA Coextruded from amixture of 50% “C” pellets Films (4 mil B layer) with 50% groundcoextruded film Total Total RI(nylon) − Example Materials Haze (%)Transmittance (%) Haze (%) Transmittance (%) RI(polyester) C-54 C 0.1291.5 0.09 91.5 n/a C-55 C/MXD6/C 1.49 91.1 16.44 87.3 0.0231 56 C/X/C0.62 91.2 0.37 91.5 0.0022

Example and Comparative Examples 57 and 58 Adhesion of Multilayer Films

ABA films were prepared by co-extruding two 15 mil layers of polyester Caround a 4 mil thick layer of either MXD6 or transamidized MXD6/30 wt %N6 blend “X.” The Nylon 6 used in the transamidized blend in thisexample was Zytel 7301. A Killian 1″ extruder was used to extrude theouter polyester C layers at a temperature of 265° C. A 0.75″ Killianextruder was used to extrude the inner layers at the temperaturesindicated in Table 8. The transamidized MXD6/30 wt % N6 blend “X” showssuperior adhesion over MXD6 to polyester C. Furthermore, improvedadhesion of the transamidized MXD6/30 wt % N6 blend to polyester C wasobtained when the inner layer melt temperature was increased from 280°C. to 285° C. MXD6 adhesion did not show any temperature dependency.

TABLE 8 “B” layer Average Peel melt Strength Example Materialstemperature g/mm C-57 C/MXD6/C 270° C. 1.74 280° C. 1.7 285° C. 1.88 58C/X/C 270° C. 4.33 280° C. 4.42 285° C. 7.14

1. A polymer composition, comprising an immiscible blend of: (i) a firstcomponent comprising at least one polyester comprising: (a) diacidresidues comprising at least 80 mole percent, based on the total diacidresidues, of the residues of at least one dicarboxylic acid selectedfrom terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid,and 1,4-cyclohexanedicarboxylic acid, and 0 to about 20 mole percent ofthe residues of at least one modifying dicarboxylic acid having 2 to 20carbon atoms; and (b) diol residues comprising at least 80 mole percent,based on the total moles of diol residues, of the residues of at leastone diol selected from ethylene glycol, 1,4-cyclohexanedimethanol;neopentyl glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol,and, 2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20mole percent of the residues of at least one modifying diol having from3 to 16 carbons; and (ii) a second component comprising a homogeneous,transamidized blend of at least two polyamides; wherein said secondcomponent (ii) and said first component (i) have a difference inrefractive index, RI(second component)−RI(first component), of about0.006 to about −0.0006, and said immiscible blend has a percenttransmittance of at least 75%, and a haze of 10% or less.
 2. Thecomposition of claim 1 wherein said diacid residues comprise theresidues of one or more dicarboxylic acids selected from terephthalicacid and isophthalic acid, and said diol residues comprise the residuesof one or more diols selected from ethylene glycol,1,4-cyclohexanedimethanol, and neopentyl glycol.
 3. The composition ofclaim 2 wherein said polyester comprises: (a) at least 80 mole percentof the residues of terephthalic acid and (b) at least 80 mole percent ofthe residues of ethylene glycol.
 4. The composition of claim 3 whichcomprises about 50 to about 99 weight percent of said first component(i) and about 50 to about 1 weight percent of said second component(ii), based on the total weight of said composition.
 5. The compositionof claim 1 which further comprises about 0.1 to about 2 mole percent,based on the total diacid residues, of the residues of at least onebranching agent selected from trimellitic acid, trimellitic anhydride,and pyromellitic dianhydride.
 6. The composition of claim 1 wherein saidhomogeneous, transamidized blend of said second component (ii) comprisesa first polyamide, comprising aromatic residues, and a different, secondpolyamide comprising aliphatic residues.
 7. The composition of claim 6wherein said first polyamide comprises the residues of m-xylylenediamineand adipic acid, and said second polyamide comprises the residues of atleast one aliphatic or cycloaliphatic monomer selected from adipic acid,pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanediocacid, dodecanedioc acid, caprolactam, butyrolactam, 11-aminoundecanediocacid, isophthalic acid, and hexamethylene diamine.
 8. The composition ofclaim 6 wherein said second polyamide comprises nylon 6, nylon 6,6, orblends thereof.
 9. A polymer composition, comprising: (A) an immiscibleblend of: (i) a first component comprising at least one polyestercomprising: (a) diacid residues comprising at least 80 mole percent,based on the total diacid residues, of the residues of at least onedicarboxylic acid selected from terephthalic acid, isophthalic acid,naphthalenedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid, and0 to about 20 mole percent of the residues of at least one modifyingdicarboxylic acid having 2 to 20 carbon atoms; and (b) diol residuescomprising at least 80 mole percent, based on the total moles of diolresidues, of the residues of at least one diol selected from ethyleneglycol, 1,4-cyclohexanedimethanol; neopentyl glycol, diethylene glycol,1,3-propanediol, 1,4-butanediol, and,2,2,4,4-tetramethyl-1,3-cyclobutanediol; and from 0 to about 20 molepercent of the residues of at least one modifying diol having from 3 to16 carbons; and (ii) a second component comprising a homogeneous,transamidized blend of at least two polyamides; and (B) at least onemetal selected from Groups 3-12, Rows 4-6 of the Periodic Table ofelements, wherein said second component (ii) and said first component(i) have a difference in refractive index, RI(second component)−RI(firstcomponent), of about 0.006 to about −0.0006, and said immiscible blendhas a percent transmittance of at least 75%, and a haze of 10% or less.10. The composition of claim 9 wherein said diacid residues comprise theresidues of one or more dicarboxylic acids selected from terephthalicacid and isophthalic acid, and said diol residues comprise the residuesof one or more diols selected from ethylene glycol,1,4-cyclohexanedimethanol, and neopentyl glycol.
 11. The composition ofclaim 10 wherein said polyester comprises: (a) at least 80 mole percentof the residues of terephthalic acid and (b) at least 80 mole percent ofthe residues of ethylene glycol.
 12. The composition of claim 11 whichcomprises about 50 to about 99 weight percent of said first component(i) and about 50 to about 1 weight percent of said second component(ii), based on the total weight of said composition.
 13. The compositionof claim 9 which further comprises about 0.1 to about 2 mole percent,based on the total diacid residues, of the residues of at least onebranching agent selected from trimellitic acid, trimellitic anhydride,and pyromellitic dianhydride.
 14. The composition of claim 9 whereinsaid homogeneous, transamidized blend of said second component (ii)comprises a first polyamide, comprising aromatic residues, and adifferent, second polyamide comprising aliphatic residues.
 15. Thecomposition of claim 14 wherein said first polyamide comprises theresidues of m-xylylenediamine and adipic acid, and said second polyamidecomprises the residues of at least one aliphatic or cycloaliphaticmonomer selected from adipic acid, pimelic acid, suberic acid, azelaicacid, sebacic acid, undecanedioc acid, dodecanedioc acid, caprolactam,butyrolactam, 11-aminoundecanedioc acid, isophthalic acid, andhexamethylene diamine.
 16. The composition of claim 14 wherein saidsecond polyamide comprises nylon 6, nylon 6,6, or blends thereof.
 17. Ashaped article comprising the composition of any one of claims 1, 3, 9,or
 11. 18. The shaped article of claim 17 which is formed by extrusion,calendering, thermoforming, blow-molding, extrusion blow-molding,injection molding, compression molding, casting, drafting, tentering, orblowing.
 19. The shaped article of claim 18 which is a sheet, film,tube, preform, or bottle.